Linux Audio

Check our new training course

Loading...
v3.15
 
   1/*
   2 * rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips.
   3 *
   4 *  Copyright (C) 2005 James Chapman (ds1337 core)
   5 *  Copyright (C) 2006 David Brownell
   6 *  Copyright (C) 2009 Matthias Fuchs (rx8025 support)
   7 *  Copyright (C) 2012 Bertrand Achard (nvram access fixes)
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 */
  13
  14#include <linux/module.h>
 
  15#include <linux/init.h>
 
 
 
 
 
  16#include <linux/slab.h>
  17#include <linux/i2c.h>
  18#include <linux/string.h>
  19#include <linux/rtc.h>
  20#include <linux/bcd.h>
  21#include <linux/rtc/ds1307.h>
 
 
  22
  23/*
  24 * We can't determine type by probing, but if we expect pre-Linux code
  25 * to have set the chip up as a clock (turning on the oscillator and
  26 * setting the date and time), Linux can ignore the non-clock features.
  27 * That's a natural job for a factory or repair bench.
  28 */
  29enum ds_type {
 
  30	ds_1307,
 
  31	ds_1337,
  32	ds_1338,
  33	ds_1339,
  34	ds_1340,
 
  35	ds_1388,
  36	ds_3231,
 
  37	m41t00,
  38	mcp7941x,
 
  39	rx_8025,
 
  40	last_ds_type /* always last */
  41	/* rs5c372 too?  different address... */
  42};
  43
  44
  45/* RTC registers don't differ much, except for the century flag */
  46#define DS1307_REG_SECS		0x00	/* 00-59 */
  47#	define DS1307_BIT_CH		0x80
  48#	define DS1340_BIT_nEOSC		0x80
  49#	define MCP7941X_BIT_ST		0x80
  50#define DS1307_REG_MIN		0x01	/* 00-59 */
 
  51#define DS1307_REG_HOUR		0x02	/* 00-23, or 1-12{am,pm} */
  52#	define DS1307_BIT_12HR		0x40	/* in REG_HOUR */
  53#	define DS1307_BIT_PM		0x20	/* in REG_HOUR */
  54#	define DS1340_BIT_CENTURY_EN	0x80	/* in REG_HOUR */
  55#	define DS1340_BIT_CENTURY	0x40	/* in REG_HOUR */
  56#define DS1307_REG_WDAY		0x03	/* 01-07 */
  57#	define MCP7941X_BIT_VBATEN	0x08
  58#define DS1307_REG_MDAY		0x04	/* 01-31 */
  59#define DS1307_REG_MONTH	0x05	/* 01-12 */
  60#	define DS1337_BIT_CENTURY	0x80	/* in REG_MONTH */
  61#define DS1307_REG_YEAR		0x06	/* 00-99 */
  62
  63/*
  64 * Other registers (control, status, alarms, trickle charge, NVRAM, etc)
  65 * start at 7, and they differ a LOT. Only control and status matter for
  66 * basic RTC date and time functionality; be careful using them.
  67 */
  68#define DS1307_REG_CONTROL	0x07		/* or ds1338 */
  69#	define DS1307_BIT_OUT		0x80
  70#	define DS1338_BIT_OSF		0x20
  71#	define DS1307_BIT_SQWE		0x10
  72#	define DS1307_BIT_RS1		0x02
  73#	define DS1307_BIT_RS0		0x01
  74#define DS1337_REG_CONTROL	0x0e
  75#	define DS1337_BIT_nEOSC		0x80
  76#	define DS1339_BIT_BBSQI		0x20
  77#	define DS3231_BIT_BBSQW		0x40 /* same as BBSQI */
  78#	define DS1337_BIT_RS2		0x10
  79#	define DS1337_BIT_RS1		0x08
  80#	define DS1337_BIT_INTCN		0x04
  81#	define DS1337_BIT_A2IE		0x02
  82#	define DS1337_BIT_A1IE		0x01
  83#define DS1340_REG_CONTROL	0x07
  84#	define DS1340_BIT_OUT		0x80
  85#	define DS1340_BIT_FT		0x40
  86#	define DS1340_BIT_CALIB_SIGN	0x20
  87#	define DS1340_M_CALIBRATION	0x1f
  88#define DS1340_REG_FLAG		0x09
  89#	define DS1340_BIT_OSF		0x80
  90#define DS1337_REG_STATUS	0x0f
  91#	define DS1337_BIT_OSF		0x80
 
  92#	define DS1337_BIT_A2I		0x02
  93#	define DS1337_BIT_A1I		0x01
  94#define DS1339_REG_ALARM1_SECS	0x07
  95
  96#define DS13XX_TRICKLE_CHARGER_MAGIC	0xa0
  97
  98#define RX8025_REG_CTRL1	0x0e
  99#	define RX8025_BIT_2412		0x20
 100#define RX8025_REG_CTRL2	0x0f
 101#	define RX8025_BIT_PON		0x10
 102#	define RX8025_BIT_VDET		0x40
 103#	define RX8025_BIT_XST		0x20
 104
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 105
 106struct ds1307 {
 107	u8			offset; /* register's offset */
 108	u8			regs[11];
 109	u16			nvram_offset;
 110	struct bin_attribute	*nvram;
 111	enum ds_type		type;
 112	unsigned long		flags;
 113#define HAS_NVRAM	0		/* bit 0 == sysfs file active */
 114#define HAS_ALARM	1		/* bit 1 == irq claimed */
 115	struct i2c_client	*client;
 116	struct rtc_device	*rtc;
 117	struct work_struct	work;
 118	s32 (*read_block_data)(const struct i2c_client *client, u8 command,
 119			       u8 length, u8 *values);
 120	s32 (*write_block_data)(const struct i2c_client *client, u8 command,
 121				u8 length, const u8 *values);
 122};
 123
 124struct chip_desc {
 125	unsigned		alarm:1;
 126	u16			nvram_offset;
 127	u16			nvram_size;
 
 
 
 
 
 
 
 128	u16			trickle_charger_reg;
 
 
 
 
 
 
 
 
 
 
 
 129};
 130
 131static const struct chip_desc chips[last_ds_type] = {
 132	[ds_1307] = {
 133		.nvram_offset	= 8,
 134		.nvram_size	= 56,
 135	},
 136	[ds_1337] = {
 137		.alarm		= 1,
 138	},
 139	[ds_1338] = {
 140		.nvram_offset	= 8,
 141		.nvram_size	= 56,
 142	},
 143	[ds_1339] = {
 144		.alarm		= 1,
 145		.trickle_charger_reg = 0x10,
 146	},
 147	[ds_1340] = {
 148		.trickle_charger_reg = 0x08,
 149	},
 150	[ds_1388] = {
 151		.trickle_charger_reg = 0x0a,
 152	},
 153	[ds_3231] = {
 154		.alarm		= 1,
 155	},
 156	[mcp7941x] = {
 157		.alarm		= 1,
 158		/* this is battery backed SRAM */
 159		.nvram_offset	= 0x20,
 160		.nvram_size	= 0x40,
 161	},
 162};
 163
 164static const struct i2c_device_id ds1307_id[] = {
 165	{ "ds1307", ds_1307 },
 166	{ "ds1337", ds_1337 },
 167	{ "ds1338", ds_1338 },
 168	{ "ds1339", ds_1339 },
 169	{ "ds1388", ds_1388 },
 170	{ "ds1340", ds_1340 },
 171	{ "ds3231", ds_3231 },
 172	{ "m41t00", m41t00 },
 173	{ "mcp7941x", mcp7941x },
 174	{ "pt7c4338", ds_1307 },
 175	{ "rx8025", rx_8025 },
 176	{ }
 177};
 178MODULE_DEVICE_TABLE(i2c, ds1307_id);
 179
 180/*----------------------------------------------------------------------*/
 181
 182#define BLOCK_DATA_MAX_TRIES 10
 183
 184static s32 ds1307_read_block_data_once(const struct i2c_client *client,
 185				       u8 command, u8 length, u8 *values)
 186{
 187	s32 i, data;
 188
 189	for (i = 0; i < length; i++) {
 190		data = i2c_smbus_read_byte_data(client, command + i);
 191		if (data < 0)
 192			return data;
 193		values[i] = data;
 194	}
 195	return i;
 196}
 197
 198static s32 ds1307_read_block_data(const struct i2c_client *client, u8 command,
 199				  u8 length, u8 *values)
 200{
 201	u8 oldvalues[255];
 202	s32 ret;
 203	int tries = 0;
 204
 205	dev_dbg(&client->dev, "ds1307_read_block_data (length=%d)\n", length);
 206	ret = ds1307_read_block_data_once(client, command, length, values);
 207	if (ret < 0)
 208		return ret;
 209	do {
 210		if (++tries > BLOCK_DATA_MAX_TRIES) {
 211			dev_err(&client->dev,
 212				"ds1307_read_block_data failed\n");
 213			return -EIO;
 214		}
 215		memcpy(oldvalues, values, length);
 216		ret = ds1307_read_block_data_once(client, command, length,
 217						  values);
 218		if (ret < 0)
 219			return ret;
 220	} while (memcmp(oldvalues, values, length));
 221	return length;
 222}
 223
 224static s32 ds1307_write_block_data(const struct i2c_client *client, u8 command,
 225				   u8 length, const u8 *values)
 226{
 227	u8 currvalues[255];
 228	int tries = 0;
 229
 230	dev_dbg(&client->dev, "ds1307_write_block_data (length=%d)\n", length);
 231	do {
 232		s32 i, ret;
 233
 234		if (++tries > BLOCK_DATA_MAX_TRIES) {
 235			dev_err(&client->dev,
 236				"ds1307_write_block_data failed\n");
 237			return -EIO;
 238		}
 239		for (i = 0; i < length; i++) {
 240			ret = i2c_smbus_write_byte_data(client, command + i,
 241							values[i]);
 242			if (ret < 0)
 243				return ret;
 244		}
 245		ret = ds1307_read_block_data_once(client, command, length,
 246						  currvalues);
 247		if (ret < 0)
 248			return ret;
 249	} while (memcmp(currvalues, values, length));
 250	return length;
 251}
 252
 253/*----------------------------------------------------------------------*/
 254
 255/* These RTC devices are not designed to be connected to a SMbus adapter.
 256   SMbus limits block operations length to 32 bytes, whereas it's not
 257   limited on I2C buses. As a result, accesses may exceed 32 bytes;
 258   in that case, split them into smaller blocks */
 259
 260static s32 ds1307_native_smbus_write_block_data(const struct i2c_client *client,
 261				u8 command, u8 length, const u8 *values)
 262{
 263	u8 suboffset = 0;
 264
 265	if (length <= I2C_SMBUS_BLOCK_MAX)
 266		return i2c_smbus_write_i2c_block_data(client,
 267					command, length, values);
 268
 269	while (suboffset < length) {
 270		s32 retval = i2c_smbus_write_i2c_block_data(client,
 271				command + suboffset,
 272				min(I2C_SMBUS_BLOCK_MAX, length - suboffset),
 273				values + suboffset);
 274		if (retval < 0)
 275			return retval;
 276
 277		suboffset += I2C_SMBUS_BLOCK_MAX;
 278	}
 279	return length;
 280}
 281
 282static s32 ds1307_native_smbus_read_block_data(const struct i2c_client *client,
 283				u8 command, u8 length, u8 *values)
 284{
 285	u8 suboffset = 0;
 286
 287	if (length <= I2C_SMBUS_BLOCK_MAX)
 288		return i2c_smbus_read_i2c_block_data(client,
 289					command, length, values);
 290
 291	while (suboffset < length) {
 292		s32 retval = i2c_smbus_read_i2c_block_data(client,
 293				command + suboffset,
 294				min(I2C_SMBUS_BLOCK_MAX, length - suboffset),
 295				values + suboffset);
 296		if (retval < 0)
 297			return retval;
 298
 299		suboffset += I2C_SMBUS_BLOCK_MAX;
 
 
 
 
 
 300	}
 301	return length;
 302}
 303
 304/*----------------------------------------------------------------------*/
 305
 306/*
 307 * The IRQ logic includes a "real" handler running in IRQ context just
 308 * long enough to schedule this workqueue entry.   We need a task context
 309 * to talk to the RTC, since I2C I/O calls require that; and disable the
 310 * IRQ until we clear its status on the chip, so that this handler can
 311 * work with any type of triggering (not just falling edge).
 312 *
 313 * The ds1337 and ds1339 both have two alarms, but we only use the first
 314 * one (with a "seconds" field).  For ds1337 we expect nINTA is our alarm
 315 * signal; ds1339 chips have only one alarm signal.
 316 */
 317static void ds1307_work(struct work_struct *work)
 318{
 319	struct ds1307		*ds1307;
 320	struct i2c_client	*client;
 321	struct mutex		*lock;
 322	int			stat, control;
 323
 324	ds1307 = container_of(work, struct ds1307, work);
 325	client = ds1307->client;
 326	lock = &ds1307->rtc->ops_lock;
 327
 328	mutex_lock(lock);
 329	stat = i2c_smbus_read_byte_data(client, DS1337_REG_STATUS);
 330	if (stat < 0)
 331		goto out;
 332
 333	if (stat & DS1337_BIT_A1I) {
 334		stat &= ~DS1337_BIT_A1I;
 335		i2c_smbus_write_byte_data(client, DS1337_REG_STATUS, stat);
 336
 337		control = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
 338		if (control < 0)
 339			goto out;
 340
 341		control &= ~DS1337_BIT_A1IE;
 342		i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, control);
 343
 344		rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
 
 
 
 
 345	}
 346
 347out:
 348	if (test_bit(HAS_ALARM, &ds1307->flags))
 349		enable_irq(client->irq);
 350	mutex_unlock(lock);
 351}
 352
 353static irqreturn_t ds1307_irq(int irq, void *dev_id)
 354{
 355	struct i2c_client	*client = dev_id;
 356	struct ds1307		*ds1307 = i2c_get_clientdata(client);
 357
 358	disable_irq_nosync(irq);
 359	schedule_work(&ds1307->work);
 360	return IRQ_HANDLED;
 361}
 362
 363/*----------------------------------------------------------------------*/
 
 
 
 
 
 
 
 
 364
 365static int ds1307_get_time(struct device *dev, struct rtc_time *t)
 366{
 367	struct ds1307	*ds1307 = dev_get_drvdata(dev);
 368	int		tmp;
 
 
 
 
 
 
 
 
 
 
 
 
 369
 370	/* read the RTC date and time registers all at once */
 371	tmp = ds1307->read_block_data(ds1307->client,
 372		ds1307->offset, 7, ds1307->regs);
 373	if (tmp != 7) {
 374		dev_err(dev, "%s error %d\n", "read", tmp);
 375		return -EIO;
 376	}
 377
 378	dev_dbg(dev, "%s: %7ph\n", "read", ds1307->regs);
 379
 380	t->tm_sec = bcd2bin(ds1307->regs[DS1307_REG_SECS] & 0x7f);
 381	t->tm_min = bcd2bin(ds1307->regs[DS1307_REG_MIN] & 0x7f);
 382	tmp = ds1307->regs[DS1307_REG_HOUR] & 0x3f;
 383	t->tm_hour = bcd2bin(tmp);
 384	t->tm_wday = bcd2bin(ds1307->regs[DS1307_REG_WDAY] & 0x07) - 1;
 385	t->tm_mday = bcd2bin(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
 386	tmp = ds1307->regs[DS1307_REG_MONTH] & 0x1f;
 
 
 
 
 387	t->tm_mon = bcd2bin(tmp) - 1;
 
 388
 389	/* assume 20YY not 19YY, and ignore DS1337_BIT_CENTURY */
 390	t->tm_year = bcd2bin(ds1307->regs[DS1307_REG_YEAR]) + 100;
 
 391
 392	dev_dbg(dev, "%s secs=%d, mins=%d, "
 393		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 394		"read", t->tm_sec, t->tm_min,
 395		t->tm_hour, t->tm_mday,
 396		t->tm_mon, t->tm_year, t->tm_wday);
 397
 398	/* initial clock setting can be undefined */
 399	return rtc_valid_tm(t);
 400}
 401
 402static int ds1307_set_time(struct device *dev, struct rtc_time *t)
 403{
 404	struct ds1307	*ds1307 = dev_get_drvdata(dev);
 
 405	int		result;
 406	int		tmp;
 407	u8		*buf = ds1307->regs;
 408
 409	dev_dbg(dev, "%s secs=%d, mins=%d, "
 410		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 411		"write", t->tm_sec, t->tm_min,
 412		t->tm_hour, t->tm_mday,
 413		t->tm_mon, t->tm_year, t->tm_wday);
 414
 415	buf[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
 416	buf[DS1307_REG_MIN] = bin2bcd(t->tm_min);
 417	buf[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
 418	buf[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
 419	buf[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
 420	buf[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 421
 422	/* assume 20YY not 19YY */
 423	tmp = t->tm_year - 100;
 424	buf[DS1307_REG_YEAR] = bin2bcd(tmp);
 
 
 
 
 
 425
 426	switch (ds1307->type) {
 427	case ds_1337:
 428	case ds_1339:
 429	case ds_3231:
 430		buf[DS1307_REG_MONTH] |= DS1337_BIT_CENTURY;
 431		break;
 432	case ds_1340:
 433		buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN
 434				| DS1340_BIT_CENTURY;
 
 
 
 
 435		break;
 436	case mcp7941x:
 437		/*
 438		 * these bits were cleared when preparing the date/time
 439		 * values and need to be set again before writing the
 440		 * buffer out to the device.
 441		 */
 442		buf[DS1307_REG_SECS] |= MCP7941X_BIT_ST;
 443		buf[DS1307_REG_WDAY] |= MCP7941X_BIT_VBATEN;
 444		break;
 445	default:
 446		break;
 447	}
 448
 449	dev_dbg(dev, "%s: %7ph\n", "write", buf);
 450
 451	result = ds1307->write_block_data(ds1307->client,
 452		ds1307->offset, 7, buf);
 453	if (result < 0) {
 454		dev_err(dev, "%s error %d\n", "write", result);
 455		return result;
 456	}
 
 
 
 
 
 
 
 
 
 
 
 457	return 0;
 458}
 459
 460static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 461{
 462	struct i2c_client       *client = to_i2c_client(dev);
 463	struct ds1307		*ds1307 = i2c_get_clientdata(client);
 464	int			ret;
 465
 466	if (!test_bit(HAS_ALARM, &ds1307->flags))
 467		return -EINVAL;
 468
 469	/* read all ALARM1, ALARM2, and status registers at once */
 470	ret = ds1307->read_block_data(client,
 471			DS1339_REG_ALARM1_SECS, 9, ds1307->regs);
 472	if (ret != 9) {
 473		dev_err(dev, "%s error %d\n", "alarm read", ret);
 474		return -EIO;
 475	}
 476
 477	dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
 478			"alarm read",
 479			ds1307->regs[0], ds1307->regs[1],
 480			ds1307->regs[2], ds1307->regs[3],
 481			ds1307->regs[4], ds1307->regs[5],
 482			ds1307->regs[6], ds1307->regs[7],
 483			ds1307->regs[8]);
 484
 485	/*
 486	 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
 487	 * and that all four fields are checked matches
 488	 */
 489	t->time.tm_sec = bcd2bin(ds1307->regs[0] & 0x7f);
 490	t->time.tm_min = bcd2bin(ds1307->regs[1] & 0x7f);
 491	t->time.tm_hour = bcd2bin(ds1307->regs[2] & 0x3f);
 492	t->time.tm_mday = bcd2bin(ds1307->regs[3] & 0x3f);
 493	t->time.tm_mon = -1;
 494	t->time.tm_year = -1;
 495	t->time.tm_wday = -1;
 496	t->time.tm_yday = -1;
 497	t->time.tm_isdst = -1;
 498
 499	/* ... and status */
 500	t->enabled = !!(ds1307->regs[7] & DS1337_BIT_A1IE);
 501	t->pending = !!(ds1307->regs[8] & DS1337_BIT_A1I);
 502
 503	dev_dbg(dev, "%s secs=%d, mins=%d, "
 504		"hours=%d, mday=%d, enabled=%d, pending=%d\n",
 505		"alarm read", t->time.tm_sec, t->time.tm_min,
 506		t->time.tm_hour, t->time.tm_mday,
 507		t->enabled, t->pending);
 508
 509	return 0;
 510}
 511
 512static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 513{
 514	struct i2c_client	*client = to_i2c_client(dev);
 515	struct ds1307		*ds1307 = i2c_get_clientdata(client);
 516	unsigned char		*buf = ds1307->regs;
 517	u8			control, status;
 518	int			ret;
 519
 520	if (!test_bit(HAS_ALARM, &ds1307->flags))
 521		return -EINVAL;
 522
 523	dev_dbg(dev, "%s secs=%d, mins=%d, "
 524		"hours=%d, mday=%d, enabled=%d, pending=%d\n",
 525		"alarm set", t->time.tm_sec, t->time.tm_min,
 526		t->time.tm_hour, t->time.tm_mday,
 527		t->enabled, t->pending);
 528
 529	/* read current status of both alarms and the chip */
 530	ret = ds1307->read_block_data(client,
 531			DS1339_REG_ALARM1_SECS, 9, buf);
 532	if (ret != 9) {
 533		dev_err(dev, "%s error %d\n", "alarm write", ret);
 534		return -EIO;
 535	}
 536	control = ds1307->regs[7];
 537	status = ds1307->regs[8];
 538
 539	dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
 540			"alarm set (old status)",
 541			ds1307->regs[0], ds1307->regs[1],
 542			ds1307->regs[2], ds1307->regs[3],
 543			ds1307->regs[4], ds1307->regs[5],
 544			ds1307->regs[6], control, status);
 545
 546	/* set ALARM1, using 24 hour and day-of-month modes */
 547	buf[0] = bin2bcd(t->time.tm_sec);
 548	buf[1] = bin2bcd(t->time.tm_min);
 549	buf[2] = bin2bcd(t->time.tm_hour);
 550	buf[3] = bin2bcd(t->time.tm_mday);
 551
 552	/* set ALARM2 to non-garbage */
 553	buf[4] = 0;
 554	buf[5] = 0;
 555	buf[6] = 0;
 
 
 
 
 
 
 
 
 
 
 
 556
 557	/* optionally enable ALARM1 */
 558	buf[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
 559	if (t->enabled) {
 560		dev_dbg(dev, "alarm IRQ armed\n");
 561		buf[7] |= DS1337_BIT_A1IE;	/* only ALARM1 is used */
 
 562	}
 563	buf[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
 564
 565	ret = ds1307->write_block_data(client,
 566			DS1339_REG_ALARM1_SECS, 9, buf);
 567	if (ret < 0) {
 568		dev_err(dev, "can't set alarm time\n");
 569		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 570	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 571
 572	return 0;
 573}
 574
 575static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
 576{
 577	struct i2c_client	*client = to_i2c_client(dev);
 578	struct ds1307		*ds1307 = i2c_get_clientdata(client);
 579	int			ret;
 580
 581	if (!test_bit(HAS_ALARM, &ds1307->flags))
 582		return -ENOTTY;
 
 
 
 583
 584	ret = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
 
 
 585	if (ret < 0)
 586		return ret;
 587
 588	if (enabled)
 589		ret |= DS1337_BIT_A1IE;
 590	else
 591		ret &= ~DS1337_BIT_A1IE;
 592
 593	ret = i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, ret);
 
 594	if (ret < 0)
 595		return ret;
 596
 597	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 598}
 599
 600static const struct rtc_class_ops ds13xx_rtc_ops = {
 601	.read_time	= ds1307_get_time,
 602	.set_time	= ds1307_set_time,
 603	.read_alarm	= ds1337_read_alarm,
 604	.set_alarm	= ds1337_set_alarm,
 605	.alarm_irq_enable = ds1307_alarm_irq_enable,
 606};
 607
 608/*----------------------------------------------------------------------*/
 
 
 609
 610/*
 611 * Alarm support for mcp7941x devices.
 612 */
 
 613
 614#define MCP7941X_REG_CONTROL		0x07
 615#	define MCP7941X_BIT_ALM0_EN	0x10
 616#	define MCP7941X_BIT_ALM1_EN	0x20
 617#define MCP7941X_REG_ALARM0_BASE	0x0a
 618#define MCP7941X_REG_ALARM0_CTRL	0x0d
 619#define MCP7941X_REG_ALARM1_BASE	0x11
 620#define MCP7941X_REG_ALARM1_CTRL	0x14
 621#	define MCP7941X_BIT_ALMX_IF	(1 << 3)
 622#	define MCP7941X_BIT_ALMX_C0	(1 << 4)
 623#	define MCP7941X_BIT_ALMX_C1	(1 << 5)
 624#	define MCP7941X_BIT_ALMX_C2	(1 << 6)
 625#	define MCP7941X_BIT_ALMX_POL	(1 << 7)
 626#	define MCP7941X_MSK_ALMX_MATCH	(MCP7941X_BIT_ALMX_C0 | \
 627					 MCP7941X_BIT_ALMX_C1 | \
 628					 MCP7941X_BIT_ALMX_C2)
 629
 630static void mcp7941x_work(struct work_struct *work)
 631{
 632	struct ds1307 *ds1307 = container_of(work, struct ds1307, work);
 633	struct i2c_client *client = ds1307->client;
 634	int reg, ret;
 635
 636	mutex_lock(&ds1307->rtc->ops_lock);
 637
 638	/* Check and clear alarm 0 interrupt flag. */
 639	reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_ALARM0_CTRL);
 640	if (reg < 0)
 641		goto out;
 642	if (!(reg & MCP7941X_BIT_ALMX_IF))
 643		goto out;
 644	reg &= ~MCP7941X_BIT_ALMX_IF;
 645	ret = i2c_smbus_write_byte_data(client, MCP7941X_REG_ALARM0_CTRL, reg);
 646	if (ret < 0)
 647		goto out;
 648
 649	/* Disable alarm 0. */
 650	reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_CONTROL);
 651	if (reg < 0)
 652		goto out;
 653	reg &= ~MCP7941X_BIT_ALM0_EN;
 654	ret = i2c_smbus_write_byte_data(client, MCP7941X_REG_CONTROL, reg);
 655	if (ret < 0)
 656		goto out;
 657
 658	rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
 659
 660out:
 661	if (test_bit(HAS_ALARM, &ds1307->flags))
 662		enable_irq(client->irq);
 663	mutex_unlock(&ds1307->rtc->ops_lock);
 664}
 665
 666static int mcp7941x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 667{
 668	struct i2c_client *client = to_i2c_client(dev);
 669	struct ds1307 *ds1307 = i2c_get_clientdata(client);
 670	u8 *regs = ds1307->regs;
 671	int ret;
 672
 673	if (!test_bit(HAS_ALARM, &ds1307->flags))
 674		return -EINVAL;
 675
 676	/* Read control and alarm 0 registers. */
 677	ret = ds1307->read_block_data(client, MCP7941X_REG_CONTROL, 10, regs);
 678	if (ret < 0)
 
 679		return ret;
 680
 681	t->enabled = !!(regs[0] & MCP7941X_BIT_ALM0_EN);
 682
 683	/* Report alarm 0 time assuming 24-hour and day-of-month modes. */
 684	t->time.tm_sec = bcd2bin(ds1307->regs[3] & 0x7f);
 685	t->time.tm_min = bcd2bin(ds1307->regs[4] & 0x7f);
 686	t->time.tm_hour = bcd2bin(ds1307->regs[5] & 0x3f);
 687	t->time.tm_wday = bcd2bin(ds1307->regs[6] & 0x7) - 1;
 688	t->time.tm_mday = bcd2bin(ds1307->regs[7] & 0x3f);
 689	t->time.tm_mon = bcd2bin(ds1307->regs[8] & 0x1f) - 1;
 690	t->time.tm_year = -1;
 691	t->time.tm_yday = -1;
 692	t->time.tm_isdst = -1;
 693
 694	dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
 695		"enabled=%d polarity=%d irq=%d match=%d\n", __func__,
 696		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 697		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,
 698		!!(ds1307->regs[6] & MCP7941X_BIT_ALMX_POL),
 699		!!(ds1307->regs[6] & MCP7941X_BIT_ALMX_IF),
 700		(ds1307->regs[6] & MCP7941X_MSK_ALMX_MATCH) >> 4);
 701
 702	return 0;
 703}
 704
 705static int mcp7941x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 
 
 
 
 706{
 707	struct i2c_client *client = to_i2c_client(dev);
 708	struct ds1307 *ds1307 = i2c_get_clientdata(client);
 709	unsigned char *regs = ds1307->regs;
 710	int ret;
 711
 712	if (!test_bit(HAS_ALARM, &ds1307->flags))
 713		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 714
 715	dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
 716		"enabled=%d pending=%d\n", __func__,
 717		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 718		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
 719		t->enabled, t->pending);
 720
 721	/* Read control and alarm 0 registers. */
 722	ret = ds1307->read_block_data(client, MCP7941X_REG_CONTROL, 10, regs);
 723	if (ret < 0)
 
 724		return ret;
 725
 726	/* Set alarm 0, using 24-hour and day-of-month modes. */
 727	regs[3] = bin2bcd(t->time.tm_sec);
 728	regs[4] = bin2bcd(t->time.tm_min);
 729	regs[5] = bin2bcd(t->time.tm_hour);
 730	regs[6] = bin2bcd(t->time.tm_wday) + 1;
 731	regs[7] = bin2bcd(t->time.tm_mday);
 732	regs[8] = bin2bcd(t->time.tm_mon) + 1;
 733
 734	/* Clear the alarm 0 interrupt flag. */
 735	regs[6] &= ~MCP7941X_BIT_ALMX_IF;
 736	/* Set alarm match: second, minute, hour, day, date, month. */
 737	regs[6] |= MCP7941X_MSK_ALMX_MATCH;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 738
 739	if (t->enabled)
 740		regs[0] |= MCP7941X_BIT_ALM0_EN;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 741	else
 742		regs[0] &= ~MCP7941X_BIT_ALM0_EN;
 743
 744	ret = ds1307->write_block_data(client, MCP7941X_REG_CONTROL, 10, regs);
 745	if (ret < 0)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 746		return ret;
 747
 748	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 749}
 750
 751static int mcp7941x_alarm_irq_enable(struct device *dev, unsigned int enabled)
 752{
 753	struct i2c_client *client = to_i2c_client(dev);
 754	struct ds1307 *ds1307 = i2c_get_clientdata(client);
 755	int reg;
 756
 757	if (!test_bit(HAS_ALARM, &ds1307->flags))
 758		return -EINVAL;
 
 759
 760	reg = i2c_smbus_read_byte_data(client, MCP7941X_REG_CONTROL);
 761	if (reg < 0)
 762		return reg;
 
 763
 764	if (enabled)
 765		reg |= MCP7941X_BIT_ALM0_EN;
 766	else
 767		reg &= ~MCP7941X_BIT_ALM0_EN;
 
 
 
 
 
 
 
 
 
 768
 769	return i2c_smbus_write_byte_data(client, MCP7941X_REG_CONTROL, reg);
 
 770}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 771
 772static const struct rtc_class_ops mcp7941x_rtc_ops = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 773	.read_time	= ds1307_get_time,
 774	.set_time	= ds1307_set_time,
 775	.read_alarm	= mcp7941x_read_alarm,
 776	.set_alarm	= mcp7941x_set_alarm,
 777	.alarm_irq_enable = mcp7941x_alarm_irq_enable,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 778};
 779
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 780/*----------------------------------------------------------------------*/
 781
 782static ssize_t
 783ds1307_nvram_read(struct file *filp, struct kobject *kobj,
 784		struct bin_attribute *attr,
 785		char *buf, loff_t off, size_t count)
 786{
 787	struct i2c_client	*client;
 788	struct ds1307		*ds1307;
 789	int			result;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 790
 791	client = kobj_to_i2c_client(kobj);
 792	ds1307 = i2c_get_clientdata(client);
 793
 794	if (unlikely(off >= ds1307->nvram->size))
 
 795		return 0;
 796	if ((off + count) > ds1307->nvram->size)
 797		count = ds1307->nvram->size - off;
 798	if (unlikely(!count))
 799		return count;
 800
 801	result = ds1307->read_block_data(client, ds1307->nvram_offset + off,
 802								count, buf);
 803	if (result < 0)
 804		dev_err(&client->dev, "%s error %d\n", "nvram read", result);
 805	return result;
 806}
 807
 808static ssize_t
 809ds1307_nvram_write(struct file *filp, struct kobject *kobj,
 810		struct bin_attribute *attr,
 811		char *buf, loff_t off, size_t count)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 812{
 813	struct i2c_client	*client;
 814	struct ds1307		*ds1307;
 815	int			result;
 
 
 
 
 
 
 
 
 
 
 
 
 
 816
 817	client = kobj_to_i2c_client(kobj);
 818	ds1307 = i2c_get_clientdata(client);
 819
 820	if (unlikely(off >= ds1307->nvram->size))
 821		return -EFBIG;
 822	if ((off + count) > ds1307->nvram->size)
 823		count = ds1307->nvram->size - off;
 824	if (unlikely(!count))
 825		return count;
 826
 827	result = ds1307->write_block_data(client, ds1307->nvram_offset + off,
 828								count, buf);
 829	if (result < 0) {
 830		dev_err(&client->dev, "%s error %d\n", "nvram write", result);
 831		return result;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 832	}
 833	return count;
 834}
 835
 
 
 
 
 
 
 
 
 836/*----------------------------------------------------------------------*/
 837
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 838static int ds1307_probe(struct i2c_client *client,
 839			const struct i2c_device_id *id)
 840{
 841	struct ds1307		*ds1307;
 
 842	int			err = -ENODEV;
 843	int			tmp;
 844	const struct chip_desc	*chip = &chips[id->driver_data];
 845	struct i2c_adapter	*adapter = to_i2c_adapter(client->dev.parent);
 846	bool			want_irq = false;
 847	unsigned char		*buf;
 848	struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
 849	static const int	bbsqi_bitpos[] = {
 850		[ds_1337] = 0,
 851		[ds_1339] = DS1339_BIT_BBSQI,
 852		[ds_3231] = DS3231_BIT_BBSQW,
 853	};
 854	const struct rtc_class_ops *rtc_ops = &ds13xx_rtc_ops;
 855
 856	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)
 857	    && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
 858		return -EIO;
 859
 860	ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL);
 861	if (!ds1307)
 862		return -ENOMEM;
 863
 864	i2c_set_clientdata(client, ds1307);
 
 
 
 
 
 
 
 
 865
 866	ds1307->client	= client;
 867	ds1307->type	= id->driver_data;
 868
 869	if (pdata && pdata->trickle_charger_setup && chip->trickle_charger_reg)
 870		i2c_smbus_write_byte_data(client, chip->trickle_charger_reg,
 871			DS13XX_TRICKLE_CHARGER_MAGIC | pdata->trickle_charger_setup);
 872
 873	buf = ds1307->regs;
 874	if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) {
 875		ds1307->read_block_data = ds1307_native_smbus_read_block_data;
 876		ds1307->write_block_data = ds1307_native_smbus_write_block_data;
 877	} else {
 878		ds1307->read_block_data = ds1307_read_block_data;
 879		ds1307->write_block_data = ds1307_write_block_data;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 880	}
 881
 
 
 
 
 
 
 
 
 
 
 
 882	switch (ds1307->type) {
 883	case ds_1337:
 884	case ds_1339:
 
 885	case ds_3231:
 886		/* get registers that the "rtc" read below won't read... */
 887		tmp = ds1307->read_block_data(ds1307->client,
 888				DS1337_REG_CONTROL, 2, buf);
 889		if (tmp != 2) {
 890			dev_dbg(&client->dev, "read error %d\n", tmp);
 891			err = -EIO;
 892			goto exit;
 893		}
 894
 895		/* oscillator off?  turn it on, so clock can tick. */
 896		if (ds1307->regs[0] & DS1337_BIT_nEOSC)
 897			ds1307->regs[0] &= ~DS1337_BIT_nEOSC;
 898
 899		/*
 900		 * Using IRQ?  Disable the square wave and both alarms.
 
 901		 * For some variants, be sure alarms can trigger when we're
 902		 * running on Vbackup (BBSQI/BBSQW)
 903		 */
 904		if (ds1307->client->irq > 0 && chip->alarm) {
 905			INIT_WORK(&ds1307->work, ds1307_work);
 906
 907			ds1307->regs[0] |= DS1337_BIT_INTCN
 908					| bbsqi_bitpos[ds1307->type];
 909			ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
 910
 911			want_irq = true;
 912		}
 913
 914		i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL,
 915							ds1307->regs[0]);
 916
 917		/* oscillator fault?  clear flag, and warn */
 918		if (ds1307->regs[1] & DS1337_BIT_OSF) {
 919			i2c_smbus_write_byte_data(client, DS1337_REG_STATUS,
 920				ds1307->regs[1] & ~DS1337_BIT_OSF);
 921			dev_warn(&client->dev, "SET TIME!\n");
 922		}
 923		break;
 924
 925	case rx_8025:
 926		tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
 927				RX8025_REG_CTRL1 << 4 | 0x08, 2, buf);
 928		if (tmp != 2) {
 929			dev_dbg(&client->dev, "read error %d\n", tmp);
 930			err = -EIO;
 931			goto exit;
 932		}
 933
 934		/* oscillator off?  turn it on, so clock can tick. */
 935		if (!(ds1307->regs[1] & RX8025_BIT_XST)) {
 936			ds1307->regs[1] |= RX8025_BIT_XST;
 937			i2c_smbus_write_byte_data(client,
 938						  RX8025_REG_CTRL2 << 4 | 0x08,
 939						  ds1307->regs[1]);
 940			dev_warn(&client->dev,
 941				 "oscillator stop detected - SET TIME!\n");
 942		}
 943
 944		if (ds1307->regs[1] & RX8025_BIT_PON) {
 945			ds1307->regs[1] &= ~RX8025_BIT_PON;
 946			i2c_smbus_write_byte_data(client,
 947						  RX8025_REG_CTRL2 << 4 | 0x08,
 948						  ds1307->regs[1]);
 949			dev_warn(&client->dev, "power-on detected\n");
 950		}
 951
 952		if (ds1307->regs[1] & RX8025_BIT_VDET) {
 953			ds1307->regs[1] &= ~RX8025_BIT_VDET;
 954			i2c_smbus_write_byte_data(client,
 955						  RX8025_REG_CTRL2 << 4 | 0x08,
 956						  ds1307->regs[1]);
 957			dev_warn(&client->dev, "voltage drop detected\n");
 958		}
 959
 960		/* make sure we are running in 24hour mode */
 961		if (!(ds1307->regs[0] & RX8025_BIT_2412)) {
 962			u8 hour;
 963
 964			/* switch to 24 hour mode */
 965			i2c_smbus_write_byte_data(client,
 966						  RX8025_REG_CTRL1 << 4 | 0x08,
 967						  ds1307->regs[0] |
 968						  RX8025_BIT_2412);
 969
 970			tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
 971					RX8025_REG_CTRL1 << 4 | 0x08, 2, buf);
 972			if (tmp != 2) {
 973				dev_dbg(&client->dev, "read error %d\n", tmp);
 974				err = -EIO;
 975				goto exit;
 976			}
 977
 978			/* correct hour */
 979			hour = bcd2bin(ds1307->regs[DS1307_REG_HOUR]);
 980			if (hour == 12)
 981				hour = 0;
 982			if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
 983				hour += 12;
 984
 985			i2c_smbus_write_byte_data(client,
 986						  DS1307_REG_HOUR << 4 | 0x08,
 987						  hour);
 988		}
 989		break;
 990	case ds_1388:
 991		ds1307->offset = 1; /* Seconds starts at 1 */
 992		break;
 993	case mcp7941x:
 994		rtc_ops = &mcp7941x_rtc_ops;
 995		if (ds1307->client->irq > 0 && chip->alarm) {
 996			INIT_WORK(&ds1307->work, mcp7941x_work);
 997			want_irq = true;
 
 
 
 998		}
 999		break;
1000	default:
1001		break;
1002	}
1003
1004read_rtc:
1005	/* read RTC registers */
1006	tmp = ds1307->read_block_data(ds1307->client, ds1307->offset, 8, buf);
1007	if (tmp != 8) {
1008		dev_dbg(&client->dev, "read error %d\n", tmp);
1009		err = -EIO;
1010		goto exit;
1011	}
1012
1013	/*
1014	 * minimal sanity checking; some chips (like DS1340) don't
1015	 * specify the extra bits as must-be-zero, but there are
1016	 * still a few values that are clearly out-of-range.
1017	 */
1018	tmp = ds1307->regs[DS1307_REG_SECS];
1019	switch (ds1307->type) {
1020	case ds_1307:
1021	case m41t00:
1022		/* clock halted?  turn it on, so clock can tick. */
1023		if (tmp & DS1307_BIT_CH) {
1024			i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
1025			dev_warn(&client->dev, "SET TIME!\n");
1026			goto read_rtc;
1027		}
1028		break;
1029	case ds_1338:
1030		/* clock halted?  turn it on, so clock can tick. */
1031		if (tmp & DS1307_BIT_CH)
1032			i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
1033
1034		/* oscillator fault?  clear flag, and warn */
1035		if (ds1307->regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {
1036			i2c_smbus_write_byte_data(client, DS1307_REG_CONTROL,
1037					ds1307->regs[DS1307_REG_CONTROL]
1038					& ~DS1338_BIT_OSF);
1039			dev_warn(&client->dev, "SET TIME!\n");
1040			goto read_rtc;
1041		}
1042		break;
1043	case ds_1340:
1044		/* clock halted?  turn it on, so clock can tick. */
1045		if (tmp & DS1340_BIT_nEOSC)
1046			i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
1047
1048		tmp = i2c_smbus_read_byte_data(client, DS1340_REG_FLAG);
1049		if (tmp < 0) {
1050			dev_dbg(&client->dev, "read error %d\n", tmp);
1051			err = -EIO;
1052			goto exit;
1053		}
1054
1055		/* oscillator fault?  clear flag, and warn */
1056		if (tmp & DS1340_BIT_OSF) {
1057			i2c_smbus_write_byte_data(client, DS1340_REG_FLAG, 0);
1058			dev_warn(&client->dev, "SET TIME!\n");
1059		}
1060		break;
1061	case mcp7941x:
1062		/* make sure that the backup battery is enabled */
1063		if (!(ds1307->regs[DS1307_REG_WDAY] & MCP7941X_BIT_VBATEN)) {
1064			i2c_smbus_write_byte_data(client, DS1307_REG_WDAY,
1065					ds1307->regs[DS1307_REG_WDAY]
1066					| MCP7941X_BIT_VBATEN);
1067		}
1068
1069		/* clock halted?  turn it on, so clock can tick. */
1070		if (!(tmp & MCP7941X_BIT_ST)) {
1071			i2c_smbus_write_byte_data(client, DS1307_REG_SECS,
1072					MCP7941X_BIT_ST);
1073			dev_warn(&client->dev, "SET TIME!\n");
1074			goto read_rtc;
1075		}
1076
1077		break;
1078	default:
1079		break;
1080	}
1081
1082	tmp = ds1307->regs[DS1307_REG_HOUR];
1083	switch (ds1307->type) {
1084	case ds_1340:
 
1085	case m41t00:
 
1086		/*
1087		 * NOTE: ignores century bits; fix before deploying
1088		 * systems that will run through year 2100.
1089		 */
1090		break;
1091	case rx_8025:
1092		break;
1093	default:
1094		if (!(tmp & DS1307_BIT_12HR))
1095			break;
1096
1097		/*
1098		 * Be sure we're in 24 hour mode.  Multi-master systems
1099		 * take note...
1100		 */
1101		tmp = bcd2bin(tmp & 0x1f);
1102		if (tmp == 12)
1103			tmp = 0;
1104		if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1105			tmp += 12;
1106		i2c_smbus_write_byte_data(client,
1107				ds1307->offset + DS1307_REG_HOUR,
1108				bin2bcd(tmp));
1109	}
1110
1111	device_set_wakeup_capable(&client->dev, want_irq);
1112	ds1307->rtc = devm_rtc_device_register(&client->dev, client->name,
1113				rtc_ops, THIS_MODULE);
1114	if (IS_ERR(ds1307->rtc)) {
1115		return PTR_ERR(ds1307->rtc);
 
 
 
 
 
 
 
 
 
 
 
1116	}
1117
1118	if (want_irq) {
1119		err = request_irq(client->irq, ds1307_irq, IRQF_SHARED,
1120			  ds1307->rtc->name, client);
 
 
1121		if (err) {
1122			client->irq = 0;
1123			dev_err(&client->dev, "unable to request IRQ!\n");
 
 
1124		} else {
1125
1126			set_bit(HAS_ALARM, &ds1307->flags);
1127			dev_dbg(&client->dev, "got IRQ %d\n", client->irq);
1128		}
1129	}
1130
1131	if (chip->nvram_size) {
1132
1133		ds1307->nvram = devm_kzalloc(&client->dev,
1134					sizeof(struct bin_attribute),
1135					GFP_KERNEL);
1136		if (!ds1307->nvram) {
1137			dev_err(&client->dev, "cannot allocate memory for nvram sysfs\n");
1138		} else {
1139
1140			ds1307->nvram->attr.name = "nvram";
1141			ds1307->nvram->attr.mode = S_IRUGO | S_IWUSR;
1142
1143			sysfs_bin_attr_init(ds1307->nvram);
1144
1145			ds1307->nvram->read = ds1307_nvram_read;
1146			ds1307->nvram->write = ds1307_nvram_write;
1147			ds1307->nvram->size = chip->nvram_size;
1148			ds1307->nvram_offset = chip->nvram_offset;
1149
1150			err = sysfs_create_bin_file(&client->dev.kobj,
1151						    ds1307->nvram);
1152			if (err) {
1153				dev_err(&client->dev,
1154					"unable to create sysfs file: %s\n",
1155					ds1307->nvram->attr.name);
1156			} else {
1157				set_bit(HAS_NVRAM, &ds1307->flags);
1158				dev_info(&client->dev, "%zu bytes nvram\n",
1159					 ds1307->nvram->size);
1160			}
1161		}
1162	}
1163
1164	return 0;
1165
1166exit:
1167	return err;
1168}
1169
1170static int ds1307_remove(struct i2c_client *client)
1171{
1172	struct ds1307 *ds1307 = i2c_get_clientdata(client);
1173
1174	if (test_and_clear_bit(HAS_ALARM, &ds1307->flags)) {
1175		free_irq(client->irq, client);
1176		cancel_work_sync(&ds1307->work);
1177	}
1178
1179	if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags))
1180		sysfs_remove_bin_file(&client->dev.kobj, ds1307->nvram);
1181
1182	return 0;
1183}
1184
1185static struct i2c_driver ds1307_driver = {
1186	.driver = {
1187		.name	= "rtc-ds1307",
1188		.owner	= THIS_MODULE,
1189	},
1190	.probe		= ds1307_probe,
1191	.remove		= ds1307_remove,
1192	.id_table	= ds1307_id,
1193};
1194
1195module_i2c_driver(ds1307_driver);
1196
1197MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
1198MODULE_LICENSE("GPL");
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips.
   4 *
   5 *  Copyright (C) 2005 James Chapman (ds1337 core)
   6 *  Copyright (C) 2006 David Brownell
   7 *  Copyright (C) 2009 Matthias Fuchs (rx8025 support)
   8 *  Copyright (C) 2012 Bertrand Achard (nvram access fixes)
 
 
 
 
   9 */
  10
  11#include <linux/bcd.h>
  12#include <linux/i2c.h>
  13#include <linux/init.h>
  14#include <linux/mod_devicetable.h>
  15#include <linux/module.h>
  16#include <linux/property.h>
  17#include <linux/rtc/ds1307.h>
  18#include <linux/rtc.h>
  19#include <linux/slab.h>
 
  20#include <linux/string.h>
  21#include <linux/hwmon.h>
  22#include <linux/hwmon-sysfs.h>
  23#include <linux/clk-provider.h>
  24#include <linux/regmap.h>
  25#include <linux/watchdog.h>
  26
  27/*
  28 * We can't determine type by probing, but if we expect pre-Linux code
  29 * to have set the chip up as a clock (turning on the oscillator and
  30 * setting the date and time), Linux can ignore the non-clock features.
  31 * That's a natural job for a factory or repair bench.
  32 */
  33enum ds_type {
  34	unknown_ds_type, /* always first and 0 */
  35	ds_1307,
  36	ds_1308,
  37	ds_1337,
  38	ds_1338,
  39	ds_1339,
  40	ds_1340,
  41	ds_1341,
  42	ds_1388,
  43	ds_3231,
  44	m41t0,
  45	m41t00,
  46	m41t11,
  47	mcp794xx,
  48	rx_8025,
  49	rx_8130,
  50	last_ds_type /* always last */
  51	/* rs5c372 too?  different address... */
  52};
  53
 
  54/* RTC registers don't differ much, except for the century flag */
  55#define DS1307_REG_SECS		0x00	/* 00-59 */
  56#	define DS1307_BIT_CH		0x80
  57#	define DS1340_BIT_nEOSC		0x80
  58#	define MCP794XX_BIT_ST		0x80
  59#define DS1307_REG_MIN		0x01	/* 00-59 */
  60#	define M41T0_BIT_OF		0x80
  61#define DS1307_REG_HOUR		0x02	/* 00-23, or 1-12{am,pm} */
  62#	define DS1307_BIT_12HR		0x40	/* in REG_HOUR */
  63#	define DS1307_BIT_PM		0x20	/* in REG_HOUR */
  64#	define DS1340_BIT_CENTURY_EN	0x80	/* in REG_HOUR */
  65#	define DS1340_BIT_CENTURY	0x40	/* in REG_HOUR */
  66#define DS1307_REG_WDAY		0x03	/* 01-07 */
  67#	define MCP794XX_BIT_VBATEN	0x08
  68#define DS1307_REG_MDAY		0x04	/* 01-31 */
  69#define DS1307_REG_MONTH	0x05	/* 01-12 */
  70#	define DS1337_BIT_CENTURY	0x80	/* in REG_MONTH */
  71#define DS1307_REG_YEAR		0x06	/* 00-99 */
  72
  73/*
  74 * Other registers (control, status, alarms, trickle charge, NVRAM, etc)
  75 * start at 7, and they differ a LOT. Only control and status matter for
  76 * basic RTC date and time functionality; be careful using them.
  77 */
  78#define DS1307_REG_CONTROL	0x07		/* or ds1338 */
  79#	define DS1307_BIT_OUT		0x80
  80#	define DS1338_BIT_OSF		0x20
  81#	define DS1307_BIT_SQWE		0x10
  82#	define DS1307_BIT_RS1		0x02
  83#	define DS1307_BIT_RS0		0x01
  84#define DS1337_REG_CONTROL	0x0e
  85#	define DS1337_BIT_nEOSC		0x80
  86#	define DS1339_BIT_BBSQI		0x20
  87#	define DS3231_BIT_BBSQW		0x40 /* same as BBSQI */
  88#	define DS1337_BIT_RS2		0x10
  89#	define DS1337_BIT_RS1		0x08
  90#	define DS1337_BIT_INTCN		0x04
  91#	define DS1337_BIT_A2IE		0x02
  92#	define DS1337_BIT_A1IE		0x01
  93#define DS1340_REG_CONTROL	0x07
  94#	define DS1340_BIT_OUT		0x80
  95#	define DS1340_BIT_FT		0x40
  96#	define DS1340_BIT_CALIB_SIGN	0x20
  97#	define DS1340_M_CALIBRATION	0x1f
  98#define DS1340_REG_FLAG		0x09
  99#	define DS1340_BIT_OSF		0x80
 100#define DS1337_REG_STATUS	0x0f
 101#	define DS1337_BIT_OSF		0x80
 102#	define DS3231_BIT_EN32KHZ	0x08
 103#	define DS1337_BIT_A2I		0x02
 104#	define DS1337_BIT_A1I		0x01
 105#define DS1339_REG_ALARM1_SECS	0x07
 106
 107#define DS13XX_TRICKLE_CHARGER_MAGIC	0xa0
 108
 109#define RX8025_REG_CTRL1	0x0e
 110#	define RX8025_BIT_2412		0x20
 111#define RX8025_REG_CTRL2	0x0f
 112#	define RX8025_BIT_PON		0x10
 113#	define RX8025_BIT_VDET		0x40
 114#	define RX8025_BIT_XST		0x20
 115
 116#define RX8130_REG_ALARM_MIN		0x17
 117#define RX8130_REG_ALARM_HOUR		0x18
 118#define RX8130_REG_ALARM_WEEK_OR_DAY	0x19
 119#define RX8130_REG_EXTENSION		0x1c
 120#define RX8130_REG_EXTENSION_WADA	BIT(3)
 121#define RX8130_REG_FLAG			0x1d
 122#define RX8130_REG_FLAG_VLF		BIT(1)
 123#define RX8130_REG_FLAG_AF		BIT(3)
 124#define RX8130_REG_CONTROL0		0x1e
 125#define RX8130_REG_CONTROL0_AIE		BIT(3)
 126#define RX8130_REG_CONTROL1		0x1f
 127#define RX8130_REG_CONTROL1_INIEN	BIT(4)
 128#define RX8130_REG_CONTROL1_CHGEN	BIT(5)
 129
 130#define MCP794XX_REG_CONTROL		0x07
 131#	define MCP794XX_BIT_ALM0_EN	0x10
 132#	define MCP794XX_BIT_ALM1_EN	0x20
 133#define MCP794XX_REG_ALARM0_BASE	0x0a
 134#define MCP794XX_REG_ALARM0_CTRL	0x0d
 135#define MCP794XX_REG_ALARM1_BASE	0x11
 136#define MCP794XX_REG_ALARM1_CTRL	0x14
 137#	define MCP794XX_BIT_ALMX_IF	BIT(3)
 138#	define MCP794XX_BIT_ALMX_C0	BIT(4)
 139#	define MCP794XX_BIT_ALMX_C1	BIT(5)
 140#	define MCP794XX_BIT_ALMX_C2	BIT(6)
 141#	define MCP794XX_BIT_ALMX_POL	BIT(7)
 142#	define MCP794XX_MSK_ALMX_MATCH	(MCP794XX_BIT_ALMX_C0 | \
 143					 MCP794XX_BIT_ALMX_C1 | \
 144					 MCP794XX_BIT_ALMX_C2)
 145
 146#define M41TXX_REG_CONTROL	0x07
 147#	define M41TXX_BIT_OUT		BIT(7)
 148#	define M41TXX_BIT_FT		BIT(6)
 149#	define M41TXX_BIT_CALIB_SIGN	BIT(5)
 150#	define M41TXX_M_CALIBRATION	GENMASK(4, 0)
 151
 152#define DS1388_REG_WDOG_HUN_SECS	0x08
 153#define DS1388_REG_WDOG_SECS		0x09
 154#define DS1388_REG_FLAG			0x0b
 155#	define DS1388_BIT_WF		BIT(6)
 156#	define DS1388_BIT_OSF		BIT(7)
 157#define DS1388_REG_CONTROL		0x0c
 158#	define DS1388_BIT_RST		BIT(0)
 159#	define DS1388_BIT_WDE		BIT(1)
 160#	define DS1388_BIT_nEOSC		BIT(7)
 161
 162/* negative offset step is -2.034ppm */
 163#define M41TXX_NEG_OFFSET_STEP_PPB	2034
 164/* positive offset step is +4.068ppm */
 165#define M41TXX_POS_OFFSET_STEP_PPB	4068
 166/* Min and max values supported with 'offset' interface by M41TXX */
 167#define M41TXX_MIN_OFFSET	((-31) * M41TXX_NEG_OFFSET_STEP_PPB)
 168#define M41TXX_MAX_OFFSET	((31) * M41TXX_POS_OFFSET_STEP_PPB)
 169
 170struct ds1307 {
 
 
 
 
 171	enum ds_type		type;
 172	struct device		*dev;
 173	struct regmap		*regmap;
 174	const char		*name;
 
 175	struct rtc_device	*rtc;
 176#ifdef CONFIG_COMMON_CLK
 177	struct clk_hw		clks[2];
 178#endif
 
 
 179};
 180
 181struct chip_desc {
 182	unsigned		alarm:1;
 183	u16			nvram_offset;
 184	u16			nvram_size;
 185	u8			offset; /* register's offset */
 186	u8			century_reg;
 187	u8			century_enable_bit;
 188	u8			century_bit;
 189	u8			bbsqi_bit;
 190	irq_handler_t		irq_handler;
 191	const struct rtc_class_ops *rtc_ops;
 192	u16			trickle_charger_reg;
 193	u8			(*do_trickle_setup)(struct ds1307 *, u32,
 194						    bool);
 195	/* Does the RTC require trickle-resistor-ohms to select the value of
 196	 * the resistor between Vcc and Vbackup?
 197	 */
 198	bool			requires_trickle_resistor;
 199	/* Some RTC's batteries and supercaps were charged by default, others
 200	 * allow charging but were not configured previously to do so.
 201	 * Remember this behavior to stay backwards compatible.
 202	 */
 203	bool			charge_default;
 204};
 205
 206static const struct chip_desc chips[last_ds_type];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 207
 208static int ds1307_get_time(struct device *dev, struct rtc_time *t)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 209{
 210	struct ds1307	*ds1307 = dev_get_drvdata(dev);
 211	int		tmp, ret;
 212	const struct chip_desc *chip = &chips[ds1307->type];
 213	u8 regs[7];
 214
 215	if (ds1307->type == rx_8130) {
 216		unsigned int regflag;
 217		ret = regmap_read(ds1307->regmap, RX8130_REG_FLAG, &regflag);
 218		if (ret) {
 219			dev_err(dev, "%s error %d\n", "read", ret);
 
 
 
 
 
 
 
 
 220			return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 221		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 222
 223		if (regflag & RX8130_REG_FLAG_VLF) {
 224			dev_warn_once(dev, "oscillator failed, set time!\n");
 225			return -EINVAL;
 226		}
 
 
 
 
 
 
 
 
 
 227	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 228
 229	/* read the RTC date and time registers all at once */
 230	ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
 231			       sizeof(regs));
 232	if (ret) {
 233		dev_err(dev, "%s error %d\n", "read", ret);
 234		return ret;
 235	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 236
 237	dev_dbg(dev, "%s: %7ph\n", "read", regs);
 
 238
 239	/* if oscillator fail bit is set, no data can be trusted */
 240	if (ds1307->type == m41t0 &&
 241	    regs[DS1307_REG_MIN] & M41T0_BIT_OF) {
 242		dev_warn_once(dev, "oscillator failed, set time!\n");
 243		return -EINVAL;
 244	}
 245
 246	tmp = regs[DS1307_REG_SECS];
 247	switch (ds1307->type) {
 248	case ds_1307:
 249	case m41t0:
 250	case m41t00:
 251	case m41t11:
 252		if (tmp & DS1307_BIT_CH)
 253			return -EINVAL;
 254		break;
 255	case ds_1308:
 256	case ds_1338:
 257		if (tmp & DS1307_BIT_CH)
 258			return -EINVAL;
 
 
 259
 260		ret = regmap_read(ds1307->regmap, DS1307_REG_CONTROL, &tmp);
 261		if (ret)
 262			return ret;
 263		if (tmp & DS1338_BIT_OSF)
 264			return -EINVAL;
 265		break;
 266	case ds_1340:
 267		if (tmp & DS1340_BIT_nEOSC)
 268			return -EINVAL;
 269
 270		ret = regmap_read(ds1307->regmap, DS1340_REG_FLAG, &tmp);
 271		if (ret)
 272			return ret;
 273		if (tmp & DS1340_BIT_OSF)
 274			return -EINVAL;
 275		break;
 276	case ds_1388:
 277		ret = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &tmp);
 278		if (ret)
 279			return ret;
 280		if (tmp & DS1388_BIT_OSF)
 281			return -EINVAL;
 282		break;
 283	case mcp794xx:
 284		if (!(tmp & MCP794XX_BIT_ST))
 285			return -EINVAL;
 286
 287		break;
 288	default:
 289		break;
 
 
 
 290	}
 291
 292	t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f);
 293	t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f);
 294	tmp = regs[DS1307_REG_HOUR] & 0x3f;
 
 
 295	t->tm_hour = bcd2bin(tmp);
 296	/* rx8130 is bit position, not BCD */
 297	if (ds1307->type == rx_8130)
 298		t->tm_wday = fls(regs[DS1307_REG_WDAY] & 0x7f);
 299	else
 300		t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1;
 301	t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f);
 302	tmp = regs[DS1307_REG_MONTH] & 0x1f;
 303	t->tm_mon = bcd2bin(tmp) - 1;
 304	t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100;
 305
 306	if (regs[chip->century_reg] & chip->century_bit &&
 307	    IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY))
 308		t->tm_year += 100;
 309
 310	dev_dbg(dev, "%s secs=%d, mins=%d, "
 311		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 312		"read", t->tm_sec, t->tm_min,
 313		t->tm_hour, t->tm_mday,
 314		t->tm_mon, t->tm_year, t->tm_wday);
 315
 316	return 0;
 
 317}
 318
 319static int ds1307_set_time(struct device *dev, struct rtc_time *t)
 320{
 321	struct ds1307	*ds1307 = dev_get_drvdata(dev);
 322	const struct chip_desc *chip = &chips[ds1307->type];
 323	int		result;
 324	int		tmp;
 325	u8		regs[7];
 326
 327	dev_dbg(dev, "%s secs=%d, mins=%d, "
 328		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
 329		"write", t->tm_sec, t->tm_min,
 330		t->tm_hour, t->tm_mday,
 331		t->tm_mon, t->tm_year, t->tm_wday);
 332
 333	if (t->tm_year < 100)
 334		return -EINVAL;
 335
 336#ifdef CONFIG_RTC_DRV_DS1307_CENTURY
 337	if (t->tm_year > (chip->century_bit ? 299 : 199))
 338		return -EINVAL;
 339#else
 340	if (t->tm_year > 199)
 341		return -EINVAL;
 342#endif
 343
 344	regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
 345	regs[DS1307_REG_MIN] = bin2bcd(t->tm_min);
 346	regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
 347	/* rx8130 is bit position, not BCD */
 348	if (ds1307->type == rx_8130)
 349		regs[DS1307_REG_WDAY] = 1 << t->tm_wday;
 350	else
 351		regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
 352	regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
 353	regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
 354
 355	/* assume 20YY not 19YY */
 356	tmp = t->tm_year - 100;
 357	regs[DS1307_REG_YEAR] = bin2bcd(tmp);
 358
 359	if (chip->century_enable_bit)
 360		regs[chip->century_reg] |= chip->century_enable_bit;
 361	if (t->tm_year > 199 && chip->century_bit)
 362		regs[chip->century_reg] |= chip->century_bit;
 363
 364	switch (ds1307->type) {
 365	case ds_1308:
 366	case ds_1338:
 367		regmap_update_bits(ds1307->regmap, DS1307_REG_CONTROL,
 368				   DS1338_BIT_OSF, 0);
 369		break;
 370	case ds_1340:
 371		regmap_update_bits(ds1307->regmap, DS1340_REG_FLAG,
 372				   DS1340_BIT_OSF, 0);
 373		break;
 374	case ds_1388:
 375		regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG,
 376				   DS1388_BIT_OSF, 0);
 377		break;
 378	case mcp794xx:
 379		/*
 380		 * these bits were cleared when preparing the date/time
 381		 * values and need to be set again before writing the
 382		 * regsfer out to the device.
 383		 */
 384		regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST;
 385		regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;
 386		break;
 387	default:
 388		break;
 389	}
 390
 391	dev_dbg(dev, "%s: %7ph\n", "write", regs);
 392
 393	result = regmap_bulk_write(ds1307->regmap, chip->offset, regs,
 394				   sizeof(regs));
 395	if (result) {
 396		dev_err(dev, "%s error %d\n", "write", result);
 397		return result;
 398	}
 399
 400	if (ds1307->type == rx_8130) {
 401		/* clear Voltage Loss Flag as data is available now */
 402		result = regmap_write(ds1307->regmap, RX8130_REG_FLAG,
 403				      ~(u8)RX8130_REG_FLAG_VLF);
 404		if (result) {
 405			dev_err(dev, "%s error %d\n", "write", result);
 406			return result;
 407		}
 408	}
 409
 410	return 0;
 411}
 412
 413static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 414{
 415	struct ds1307		*ds1307 = dev_get_drvdata(dev);
 
 416	int			ret;
 417	u8			regs[9];
 
 
 418
 419	/* read all ALARM1, ALARM2, and status registers at once */
 420	ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS,
 421			       regs, sizeof(regs));
 422	if (ret) {
 423		dev_err(dev, "%s error %d\n", "alarm read", ret);
 424		return ret;
 425	}
 426
 427	dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",
 428		&regs[0], &regs[4], &regs[7]);
 
 
 
 
 
 429
 430	/*
 431	 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
 432	 * and that all four fields are checked matches
 433	 */
 434	t->time.tm_sec = bcd2bin(regs[0] & 0x7f);
 435	t->time.tm_min = bcd2bin(regs[1] & 0x7f);
 436	t->time.tm_hour = bcd2bin(regs[2] & 0x3f);
 437	t->time.tm_mday = bcd2bin(regs[3] & 0x3f);
 
 
 
 
 
 438
 439	/* ... and status */
 440	t->enabled = !!(regs[7] & DS1337_BIT_A1IE);
 441	t->pending = !!(regs[8] & DS1337_BIT_A1I);
 442
 443	dev_dbg(dev, "%s secs=%d, mins=%d, "
 444		"hours=%d, mday=%d, enabled=%d, pending=%d\n",
 445		"alarm read", t->time.tm_sec, t->time.tm_min,
 446		t->time.tm_hour, t->time.tm_mday,
 447		t->enabled, t->pending);
 448
 449	return 0;
 450}
 451
 452static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 453{
 454	struct ds1307		*ds1307 = dev_get_drvdata(dev);
 455	unsigned char		regs[9];
 
 456	u8			control, status;
 457	int			ret;
 458
 
 
 
 459	dev_dbg(dev, "%s secs=%d, mins=%d, "
 460		"hours=%d, mday=%d, enabled=%d, pending=%d\n",
 461		"alarm set", t->time.tm_sec, t->time.tm_min,
 462		t->time.tm_hour, t->time.tm_mday,
 463		t->enabled, t->pending);
 464
 465	/* read current status of both alarms and the chip */
 466	ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
 467			       sizeof(regs));
 468	if (ret) {
 469		dev_err(dev, "%s error %d\n", "alarm write", ret);
 470		return ret;
 471	}
 472	control = regs[7];
 473	status = regs[8];
 474
 475	dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",
 476		&regs[0], &regs[4], control, status);
 
 
 
 
 477
 478	/* set ALARM1, using 24 hour and day-of-month modes */
 479	regs[0] = bin2bcd(t->time.tm_sec);
 480	regs[1] = bin2bcd(t->time.tm_min);
 481	regs[2] = bin2bcd(t->time.tm_hour);
 482	regs[3] = bin2bcd(t->time.tm_mday);
 483
 484	/* set ALARM2 to non-garbage */
 485	regs[4] = 0;
 486	regs[5] = 0;
 487	regs[6] = 0;
 488
 489	/* disable alarms */
 490	regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
 491	regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
 492
 493	ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
 494				sizeof(regs));
 495	if (ret) {
 496		dev_err(dev, "can't set alarm time\n");
 497		return ret;
 498	}
 499
 500	/* optionally enable ALARM1 */
 
 501	if (t->enabled) {
 502		dev_dbg(dev, "alarm IRQ armed\n");
 503		regs[7] |= DS1337_BIT_A1IE;	/* only ALARM1 is used */
 504		regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]);
 505	}
 
 506
 507	return 0;
 508}
 509
 510static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
 511{
 512	struct ds1307		*ds1307 = dev_get_drvdata(dev);
 513
 514	return regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
 515				  DS1337_BIT_A1IE,
 516				  enabled ? DS1337_BIT_A1IE : 0);
 517}
 518
 519static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode)
 520{
 521	u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
 522		DS1307_TRICKLE_CHARGER_NO_DIODE;
 523
 524	setup |= DS13XX_TRICKLE_CHARGER_MAGIC;
 525
 526	switch (ohms) {
 527	case 250:
 528		setup |= DS1307_TRICKLE_CHARGER_250_OHM;
 529		break;
 530	case 2000:
 531		setup |= DS1307_TRICKLE_CHARGER_2K_OHM;
 532		break;
 533	case 4000:
 534		setup |= DS1307_TRICKLE_CHARGER_4K_OHM;
 535		break;
 536	default:
 537		dev_warn(ds1307->dev,
 538			 "Unsupported ohm value %u in dt\n", ohms);
 539		return 0;
 540	}
 541	return setup;
 542}
 543
 544static u8 do_trickle_setup_rx8130(struct ds1307 *ds1307, u32 ohms, bool diode)
 545{
 546	/* make sure that the backup battery is enabled */
 547	u8 setup = RX8130_REG_CONTROL1_INIEN;
 548	if (diode)
 549		setup |= RX8130_REG_CONTROL1_CHGEN;
 550
 551	return setup;
 552}
 553
 554static irqreturn_t rx8130_irq(int irq, void *dev_id)
 555{
 556	struct ds1307           *ds1307 = dev_id;
 557	u8 ctl[3];
 558	int ret;
 559
 560	rtc_lock(ds1307->rtc);
 561
 562	/* Read control registers. */
 563	ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
 564			       sizeof(ctl));
 565	if (ret < 0)
 566		goto out;
 567	if (!(ctl[1] & RX8130_REG_FLAG_AF))
 568		goto out;
 569	ctl[1] &= ~RX8130_REG_FLAG_AF;
 570	ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
 571
 572	ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
 573				sizeof(ctl));
 574	if (ret < 0)
 575		goto out;
 576
 577	rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
 578
 579out:
 580	rtc_unlock(ds1307->rtc);
 581
 582	return IRQ_HANDLED;
 583}
 584
 585static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 586{
 587	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 588	u8 ald[3], ctl[3];
 589	int ret;
 590
 591	/* Read alarm registers. */
 592	ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
 593			       sizeof(ald));
 594	if (ret < 0)
 595		return ret;
 596
 597	/* Read control registers. */
 598	ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
 599			       sizeof(ctl));
 600	if (ret < 0)
 601		return ret;
 602
 603	t->enabled = !!(ctl[2] & RX8130_REG_CONTROL0_AIE);
 604	t->pending = !!(ctl[1] & RX8130_REG_FLAG_AF);
 605
 606	/* Report alarm 0 time assuming 24-hour and day-of-month modes. */
 607	t->time.tm_sec = -1;
 608	t->time.tm_min = bcd2bin(ald[0] & 0x7f);
 609	t->time.tm_hour = bcd2bin(ald[1] & 0x7f);
 610	t->time.tm_wday = -1;
 611	t->time.tm_mday = bcd2bin(ald[2] & 0x7f);
 612	t->time.tm_mon = -1;
 613	t->time.tm_year = -1;
 614	t->time.tm_yday = -1;
 615	t->time.tm_isdst = -1;
 616
 617	dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d enabled=%d\n",
 618		__func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 619		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled);
 620
 621	return 0;
 622}
 623
 624static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 625{
 626	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 627	u8 ald[3], ctl[3];
 628	int ret;
 629
 630	dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
 631		"enabled=%d pending=%d\n", __func__,
 632		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 633		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
 634		t->enabled, t->pending);
 635
 636	/* Read control registers. */
 637	ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
 638			       sizeof(ctl));
 639	if (ret < 0)
 640		return ret;
 641
 642	ctl[0] &= RX8130_REG_EXTENSION_WADA;
 643	ctl[1] &= ~RX8130_REG_FLAG_AF;
 644	ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
 
 645
 646	ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
 647				sizeof(ctl));
 648	if (ret < 0)
 649		return ret;
 650
 651	/* Hardware alarm precision is 1 minute! */
 652	ald[0] = bin2bcd(t->time.tm_min);
 653	ald[1] = bin2bcd(t->time.tm_hour);
 654	ald[2] = bin2bcd(t->time.tm_mday);
 655
 656	ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
 657				sizeof(ald));
 658	if (ret < 0)
 659		return ret;
 660
 661	if (!t->enabled)
 662		return 0;
 663
 664	ctl[2] |= RX8130_REG_CONTROL0_AIE;
 665
 666	return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, ctl[2]);
 667}
 668
 669static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled)
 670{
 671	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 672	int ret, reg;
 
 
 
 673
 674	ret = regmap_read(ds1307->regmap, RX8130_REG_CONTROL0, &reg);
 675	if (ret < 0)
 676		return ret;
 677
 678	if (enabled)
 679		reg |= RX8130_REG_CONTROL0_AIE;
 680	else
 681		reg &= ~RX8130_REG_CONTROL0_AIE;
 682
 683	return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg);
 684}
 
 
 
 
 
 
 
 
 
 
 
 
 
 685
 686static irqreturn_t mcp794xx_irq(int irq, void *dev_id)
 687{
 688	struct ds1307           *ds1307 = dev_id;
 689	struct mutex            *lock = &ds1307->rtc->ops_lock;
 690	int reg, ret;
 691
 692	mutex_lock(lock);
 693
 694	/* Check and clear alarm 0 interrupt flag. */
 695	ret = regmap_read(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, &reg);
 696	if (ret)
 697		goto out;
 698	if (!(reg & MCP794XX_BIT_ALMX_IF))
 699		goto out;
 700	reg &= ~MCP794XX_BIT_ALMX_IF;
 701	ret = regmap_write(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, reg);
 702	if (ret)
 703		goto out;
 704
 705	/* Disable alarm 0. */
 706	ret = regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
 707				 MCP794XX_BIT_ALM0_EN, 0);
 708	if (ret)
 
 
 
 709		goto out;
 710
 711	rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
 712
 713out:
 714	mutex_unlock(lock);
 715
 716	return IRQ_HANDLED;
 717}
 718
 719static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 720{
 721	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 722	u8 regs[10];
 
 723	int ret;
 724
 
 
 
 725	/* Read control and alarm 0 registers. */
 726	ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
 727			       sizeof(regs));
 728	if (ret)
 729		return ret;
 730
 731	t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN);
 732
 733	/* Report alarm 0 time assuming 24-hour and day-of-month modes. */
 734	t->time.tm_sec = bcd2bin(regs[3] & 0x7f);
 735	t->time.tm_min = bcd2bin(regs[4] & 0x7f);
 736	t->time.tm_hour = bcd2bin(regs[5] & 0x3f);
 737	t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1;
 738	t->time.tm_mday = bcd2bin(regs[7] & 0x3f);
 739	t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1;
 740	t->time.tm_year = -1;
 741	t->time.tm_yday = -1;
 742	t->time.tm_isdst = -1;
 743
 744	dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
 745		"enabled=%d polarity=%d irq=%d match=%lu\n", __func__,
 746		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 747		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,
 748		!!(regs[6] & MCP794XX_BIT_ALMX_POL),
 749		!!(regs[6] & MCP794XX_BIT_ALMX_IF),
 750		(regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);
 751
 752	return 0;
 753}
 754
 755/*
 756 * We may have a random RTC weekday, therefore calculate alarm weekday based
 757 * on current weekday we read from the RTC timekeeping regs
 758 */
 759static int mcp794xx_alm_weekday(struct device *dev, struct rtc_time *tm_alarm)
 760{
 761	struct rtc_time tm_now;
 762	int days_now, days_alarm, ret;
 
 
 763
 764	ret = ds1307_get_time(dev, &tm_now);
 765	if (ret)
 766		return ret;
 767
 768	days_now = div_s64(rtc_tm_to_time64(&tm_now), 24 * 60 * 60);
 769	days_alarm = div_s64(rtc_tm_to_time64(tm_alarm), 24 * 60 * 60);
 770
 771	return (tm_now.tm_wday + days_alarm - days_now) % 7 + 1;
 772}
 773
 774static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 775{
 776	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 777	unsigned char regs[10];
 778	int wday, ret;
 779
 780	wday = mcp794xx_alm_weekday(dev, &t->time);
 781	if (wday < 0)
 782		return wday;
 783
 784	dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
 785		"enabled=%d pending=%d\n", __func__,
 786		t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
 787		t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
 788		t->enabled, t->pending);
 789
 790	/* Read control and alarm 0 registers. */
 791	ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
 792			       sizeof(regs));
 793	if (ret)
 794		return ret;
 795
 796	/* Set alarm 0, using 24-hour and day-of-month modes. */
 797	regs[3] = bin2bcd(t->time.tm_sec);
 798	regs[4] = bin2bcd(t->time.tm_min);
 799	regs[5] = bin2bcd(t->time.tm_hour);
 800	regs[6] = wday;
 801	regs[7] = bin2bcd(t->time.tm_mday);
 802	regs[8] = bin2bcd(t->time.tm_mon + 1);
 803
 804	/* Clear the alarm 0 interrupt flag. */
 805	regs[6] &= ~MCP794XX_BIT_ALMX_IF;
 806	/* Set alarm match: second, minute, hour, day, date, month. */
 807	regs[6] |= MCP794XX_MSK_ALMX_MATCH;
 808	/* Disable interrupt. We will not enable until completely programmed */
 809	regs[0] &= ~MCP794XX_BIT_ALM0_EN;
 810
 811	ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
 812				sizeof(regs));
 813	if (ret)
 814		return ret;
 815
 816	if (!t->enabled)
 817		return 0;
 818	regs[0] |= MCP794XX_BIT_ALM0_EN;
 819	return regmap_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs[0]);
 820}
 821
 822static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled)
 823{
 824	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 825
 826	return regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
 827				  MCP794XX_BIT_ALM0_EN,
 828				  enabled ? MCP794XX_BIT_ALM0_EN : 0);
 829}
 830
 831static int m41txx_rtc_read_offset(struct device *dev, long *offset)
 832{
 833	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 834	unsigned int ctrl_reg;
 835	u8 val;
 836
 837	regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg);
 838
 839	val = ctrl_reg & M41TXX_M_CALIBRATION;
 840
 841	/* check if positive */
 842	if (ctrl_reg & M41TXX_BIT_CALIB_SIGN)
 843		*offset = (val * M41TXX_POS_OFFSET_STEP_PPB);
 844	else
 845		*offset = -(val * M41TXX_NEG_OFFSET_STEP_PPB);
 846
 847	return 0;
 848}
 849
 850static int m41txx_rtc_set_offset(struct device *dev, long offset)
 851{
 852	struct ds1307 *ds1307 = dev_get_drvdata(dev);
 853	unsigned int ctrl_reg;
 854
 855	if ((offset < M41TXX_MIN_OFFSET) || (offset > M41TXX_MAX_OFFSET))
 856		return -ERANGE;
 857
 858	if (offset >= 0) {
 859		ctrl_reg = DIV_ROUND_CLOSEST(offset,
 860					     M41TXX_POS_OFFSET_STEP_PPB);
 861		ctrl_reg |= M41TXX_BIT_CALIB_SIGN;
 862	} else {
 863		ctrl_reg = DIV_ROUND_CLOSEST(abs(offset),
 864					     M41TXX_NEG_OFFSET_STEP_PPB);
 865	}
 866
 867	return regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL,
 868				  M41TXX_M_CALIBRATION | M41TXX_BIT_CALIB_SIGN,
 869				  ctrl_reg);
 870}
 871
 872#ifdef CONFIG_WATCHDOG_CORE
 873static int ds1388_wdt_start(struct watchdog_device *wdt_dev)
 874{
 875	struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev);
 876	u8 regs[2];
 877	int ret;
 878
 879	ret = regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG,
 880				 DS1388_BIT_WF, 0);
 881	if (ret)
 882		return ret;
 883
 884	ret = regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL,
 885				 DS1388_BIT_WDE | DS1388_BIT_RST, 0);
 886	if (ret)
 887		return ret;
 888
 889	/*
 890	 * watchdog timeouts are measured in seconds. So ignore hundredths of
 891	 * seconds field.
 892	 */
 893	regs[0] = 0;
 894	regs[1] = bin2bcd(wdt_dev->timeout);
 895
 896	ret = regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs,
 897				sizeof(regs));
 898	if (ret)
 899		return ret;
 900
 901	return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL,
 902				  DS1388_BIT_WDE | DS1388_BIT_RST,
 903				  DS1388_BIT_WDE | DS1388_BIT_RST);
 904}
 905
 906static int ds1388_wdt_stop(struct watchdog_device *wdt_dev)
 907{
 908	struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev);
 
 
 909
 910	return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL,
 911				  DS1388_BIT_WDE | DS1388_BIT_RST, 0);
 912}
 913
 914static int ds1388_wdt_ping(struct watchdog_device *wdt_dev)
 915{
 916	struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev);
 917	u8 regs[2];
 918
 919	return regmap_bulk_read(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs,
 920				sizeof(regs));
 921}
 922
 923static int ds1388_wdt_set_timeout(struct watchdog_device *wdt_dev,
 924				  unsigned int val)
 925{
 926	struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev);
 927	u8 regs[2];
 928
 929	wdt_dev->timeout = val;
 930	regs[0] = 0;
 931	regs[1] = bin2bcd(wdt_dev->timeout);
 932
 933	return regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs,
 934				 sizeof(regs));
 935}
 936#endif
 937
 938static const struct rtc_class_ops rx8130_rtc_ops = {
 939	.read_time      = ds1307_get_time,
 940	.set_time       = ds1307_set_time,
 941	.read_alarm     = rx8130_read_alarm,
 942	.set_alarm      = rx8130_set_alarm,
 943	.alarm_irq_enable = rx8130_alarm_irq_enable,
 944};
 945
 946static const struct rtc_class_ops mcp794xx_rtc_ops = {
 947	.read_time      = ds1307_get_time,
 948	.set_time       = ds1307_set_time,
 949	.read_alarm     = mcp794xx_read_alarm,
 950	.set_alarm      = mcp794xx_set_alarm,
 951	.alarm_irq_enable = mcp794xx_alarm_irq_enable,
 952};
 953
 954static const struct rtc_class_ops m41txx_rtc_ops = {
 955	.read_time      = ds1307_get_time,
 956	.set_time       = ds1307_set_time,
 957	.read_alarm	= ds1337_read_alarm,
 958	.set_alarm	= ds1337_set_alarm,
 959	.alarm_irq_enable = ds1307_alarm_irq_enable,
 960	.read_offset	= m41txx_rtc_read_offset,
 961	.set_offset	= m41txx_rtc_set_offset,
 962};
 963
 964static const struct chip_desc chips[last_ds_type] = {
 965	[ds_1307] = {
 966		.nvram_offset	= 8,
 967		.nvram_size	= 56,
 968	},
 969	[ds_1308] = {
 970		.nvram_offset	= 8,
 971		.nvram_size	= 56,
 972	},
 973	[ds_1337] = {
 974		.alarm		= 1,
 975		.century_reg	= DS1307_REG_MONTH,
 976		.century_bit	= DS1337_BIT_CENTURY,
 977	},
 978	[ds_1338] = {
 979		.nvram_offset	= 8,
 980		.nvram_size	= 56,
 981	},
 982	[ds_1339] = {
 983		.alarm		= 1,
 984		.century_reg	= DS1307_REG_MONTH,
 985		.century_bit	= DS1337_BIT_CENTURY,
 986		.bbsqi_bit	= DS1339_BIT_BBSQI,
 987		.trickle_charger_reg = 0x10,
 988		.do_trickle_setup = &do_trickle_setup_ds1339,
 989		.requires_trickle_resistor = true,
 990		.charge_default = true,
 991	},
 992	[ds_1340] = {
 993		.century_reg	= DS1307_REG_HOUR,
 994		.century_enable_bit = DS1340_BIT_CENTURY_EN,
 995		.century_bit	= DS1340_BIT_CENTURY,
 996		.do_trickle_setup = &do_trickle_setup_ds1339,
 997		.trickle_charger_reg = 0x08,
 998		.requires_trickle_resistor = true,
 999		.charge_default = true,
1000	},
1001	[ds_1341] = {
1002		.century_reg	= DS1307_REG_MONTH,
1003		.century_bit	= DS1337_BIT_CENTURY,
1004	},
1005	[ds_1388] = {
1006		.offset		= 1,
1007		.trickle_charger_reg = 0x0a,
1008	},
1009	[ds_3231] = {
1010		.alarm		= 1,
1011		.century_reg	= DS1307_REG_MONTH,
1012		.century_bit	= DS1337_BIT_CENTURY,
1013		.bbsqi_bit	= DS3231_BIT_BBSQW,
1014	},
1015	[rx_8130] = {
1016		.alarm		= 1,
1017		/* this is battery backed SRAM */
1018		.nvram_offset	= 0x20,
1019		.nvram_size	= 4,	/* 32bit (4 word x 8 bit) */
1020		.offset		= 0x10,
1021		.irq_handler = rx8130_irq,
1022		.rtc_ops = &rx8130_rtc_ops,
1023		.trickle_charger_reg = RX8130_REG_CONTROL1,
1024		.do_trickle_setup = &do_trickle_setup_rx8130,
1025	},
1026	[m41t0] = {
1027		.rtc_ops	= &m41txx_rtc_ops,
1028	},
1029	[m41t00] = {
1030		.rtc_ops	= &m41txx_rtc_ops,
1031	},
1032	[m41t11] = {
1033		/* this is battery backed SRAM */
1034		.nvram_offset	= 8,
1035		.nvram_size	= 56,
1036		.rtc_ops	= &m41txx_rtc_ops,
1037	},
1038	[mcp794xx] = {
1039		.alarm		= 1,
1040		/* this is battery backed SRAM */
1041		.nvram_offset	= 0x20,
1042		.nvram_size	= 0x40,
1043		.irq_handler = mcp794xx_irq,
1044		.rtc_ops = &mcp794xx_rtc_ops,
1045	},
1046};
1047
1048static const struct i2c_device_id ds1307_id[] = {
1049	{ "ds1307", ds_1307 },
1050	{ "ds1308", ds_1308 },
1051	{ "ds1337", ds_1337 },
1052	{ "ds1338", ds_1338 },
1053	{ "ds1339", ds_1339 },
1054	{ "ds1388", ds_1388 },
1055	{ "ds1340", ds_1340 },
1056	{ "ds1341", ds_1341 },
1057	{ "ds3231", ds_3231 },
1058	{ "m41t0", m41t0 },
1059	{ "m41t00", m41t00 },
1060	{ "m41t11", m41t11 },
1061	{ "mcp7940x", mcp794xx },
1062	{ "mcp7941x", mcp794xx },
1063	{ "pt7c4338", ds_1307 },
1064	{ "rx8025", rx_8025 },
1065	{ "isl12057", ds_1337 },
1066	{ "rx8130", rx_8130 },
1067	{ }
1068};
1069MODULE_DEVICE_TABLE(i2c, ds1307_id);
1070
1071static const struct of_device_id ds1307_of_match[] = {
1072	{
1073		.compatible = "dallas,ds1307",
1074		.data = (void *)ds_1307
1075	},
1076	{
1077		.compatible = "dallas,ds1308",
1078		.data = (void *)ds_1308
1079	},
1080	{
1081		.compatible = "dallas,ds1337",
1082		.data = (void *)ds_1337
1083	},
1084	{
1085		.compatible = "dallas,ds1338",
1086		.data = (void *)ds_1338
1087	},
1088	{
1089		.compatible = "dallas,ds1339",
1090		.data = (void *)ds_1339
1091	},
1092	{
1093		.compatible = "dallas,ds1388",
1094		.data = (void *)ds_1388
1095	},
1096	{
1097		.compatible = "dallas,ds1340",
1098		.data = (void *)ds_1340
1099	},
1100	{
1101		.compatible = "dallas,ds1341",
1102		.data = (void *)ds_1341
1103	},
1104	{
1105		.compatible = "maxim,ds3231",
1106		.data = (void *)ds_3231
1107	},
1108	{
1109		.compatible = "st,m41t0",
1110		.data = (void *)m41t0
1111	},
1112	{
1113		.compatible = "st,m41t00",
1114		.data = (void *)m41t00
1115	},
1116	{
1117		.compatible = "st,m41t11",
1118		.data = (void *)m41t11
1119	},
1120	{
1121		.compatible = "microchip,mcp7940x",
1122		.data = (void *)mcp794xx
1123	},
1124	{
1125		.compatible = "microchip,mcp7941x",
1126		.data = (void *)mcp794xx
1127	},
1128	{
1129		.compatible = "pericom,pt7c4338",
1130		.data = (void *)ds_1307
1131	},
1132	{
1133		.compatible = "epson,rx8025",
1134		.data = (void *)rx_8025
1135	},
1136	{
1137		.compatible = "isil,isl12057",
1138		.data = (void *)ds_1337
1139	},
1140	{
1141		.compatible = "epson,rx8130",
1142		.data = (void *)rx_8130
1143	},
1144	{ }
1145};
1146MODULE_DEVICE_TABLE(of, ds1307_of_match);
1147
1148/*
1149 * The ds1337 and ds1339 both have two alarms, but we only use the first
1150 * one (with a "seconds" field).  For ds1337 we expect nINTA is our alarm
1151 * signal; ds1339 chips have only one alarm signal.
1152 */
1153static irqreturn_t ds1307_irq(int irq, void *dev_id)
1154{
1155	struct ds1307		*ds1307 = dev_id;
1156	struct mutex		*lock = &ds1307->rtc->ops_lock;
1157	int			stat, ret;
1158
1159	mutex_lock(lock);
1160	ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat);
1161	if (ret)
1162		goto out;
1163
1164	if (stat & DS1337_BIT_A1I) {
1165		stat &= ~DS1337_BIT_A1I;
1166		regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat);
1167
1168		ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
1169					 DS1337_BIT_A1IE, 0);
1170		if (ret)
1171			goto out;
1172
1173		rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
1174	}
1175
1176out:
1177	mutex_unlock(lock);
1178
1179	return IRQ_HANDLED;
1180}
1181
1182/*----------------------------------------------------------------------*/
1183
1184static const struct rtc_class_ops ds13xx_rtc_ops = {
1185	.read_time	= ds1307_get_time,
1186	.set_time	= ds1307_set_time,
1187	.read_alarm	= ds1337_read_alarm,
1188	.set_alarm	= ds1337_set_alarm,
1189	.alarm_irq_enable = ds1307_alarm_irq_enable,
1190};
1191
1192static ssize_t frequency_test_store(struct device *dev,
1193				    struct device_attribute *attr,
1194				    const char *buf, size_t count)
1195{
1196	struct ds1307 *ds1307 = dev_get_drvdata(dev->parent);
1197	bool freq_test_en;
1198	int ret;
1199
1200	ret = kstrtobool(buf, &freq_test_en);
1201	if (ret) {
1202		dev_err(dev, "Failed to store RTC Frequency Test attribute\n");
1203		return ret;
1204	}
1205
1206	regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT,
1207			   freq_test_en ? M41TXX_BIT_FT : 0);
1208
1209	return count;
1210}
1211
1212static ssize_t frequency_test_show(struct device *dev,
1213				   struct device_attribute *attr,
1214				   char *buf)
1215{
1216	struct ds1307 *ds1307 = dev_get_drvdata(dev->parent);
1217	unsigned int ctrl_reg;
1218
1219	regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg);
1220
1221	return scnprintf(buf, PAGE_SIZE, (ctrl_reg & M41TXX_BIT_FT) ? "on\n" :
1222			"off\n");
1223}
1224
1225static DEVICE_ATTR_RW(frequency_test);
1226
1227static struct attribute *rtc_freq_test_attrs[] = {
1228	&dev_attr_frequency_test.attr,
1229	NULL,
1230};
1231
1232static const struct attribute_group rtc_freq_test_attr_group = {
1233	.attrs		= rtc_freq_test_attrs,
1234};
1235
1236static int ds1307_add_frequency_test(struct ds1307 *ds1307)
1237{
1238	int err;
1239
1240	switch (ds1307->type) {
1241	case m41t0:
1242	case m41t00:
1243	case m41t11:
1244		err = rtc_add_group(ds1307->rtc, &rtc_freq_test_attr_group);
1245		if (err)
1246			return err;
1247		break;
1248	default:
1249		break;
1250	}
1251
1252	return 0;
1253}
1254
1255/*----------------------------------------------------------------------*/
1256
1257static int ds1307_nvram_read(void *priv, unsigned int offset, void *val,
1258			     size_t bytes)
 
 
1259{
1260	struct ds1307 *ds1307 = priv;
1261	const struct chip_desc *chip = &chips[ds1307->type];
1262
1263	return regmap_bulk_read(ds1307->regmap, chip->nvram_offset + offset,
1264				val, bytes);
1265}
1266
1267static int ds1307_nvram_write(void *priv, unsigned int offset, void *val,
1268			      size_t bytes)
1269{
1270	struct ds1307 *ds1307 = priv;
1271	const struct chip_desc *chip = &chips[ds1307->type];
1272
1273	return regmap_bulk_write(ds1307->regmap, chip->nvram_offset + offset,
1274				 val, bytes);
1275}
1276
1277/*----------------------------------------------------------------------*/
1278
1279static u8 ds1307_trickle_init(struct ds1307 *ds1307,
1280			      const struct chip_desc *chip)
1281{
1282	u32 ohms, chargeable;
1283	bool diode = chip->charge_default;
1284
1285	if (!chip->do_trickle_setup)
1286		return 0;
1287
1288	if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms",
1289				     &ohms) && chip->requires_trickle_resistor)
1290		return 0;
1291
1292	/* aux-voltage-chargeable takes precedence over the deprecated
1293	 * trickle-diode-disable
1294	 */
1295	if (!device_property_read_u32(ds1307->dev, "aux-voltage-chargeable",
1296				     &chargeable)) {
1297		switch (chargeable) {
1298		case 0:
1299			diode = false;
1300			break;
1301		case 1:
1302			diode = true;
1303			break;
1304		default:
1305			dev_warn(ds1307->dev,
1306				 "unsupported aux-voltage-chargeable value\n");
1307			break;
1308		}
1309	} else if (device_property_read_bool(ds1307->dev,
1310					     "trickle-diode-disable")) {
1311		diode = false;
1312	}
1313
1314	return chip->do_trickle_setup(ds1307, ohms, diode);
1315}
1316
1317/*----------------------------------------------------------------------*/
1318
1319#if IS_REACHABLE(CONFIG_HWMON)
1320
1321/*
1322 * Temperature sensor support for ds3231 devices.
1323 */
1324
1325#define DS3231_REG_TEMPERATURE	0x11
1326
1327/*
1328 * A user-initiated temperature conversion is not started by this function,
1329 * so the temperature is updated once every 64 seconds.
1330 */
1331static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC)
1332{
1333	struct ds1307 *ds1307 = dev_get_drvdata(dev);
1334	u8 temp_buf[2];
1335	s16 temp;
1336	int ret;
1337
1338	ret = regmap_bulk_read(ds1307->regmap, DS3231_REG_TEMPERATURE,
1339			       temp_buf, sizeof(temp_buf));
1340	if (ret)
1341		return ret;
1342	/*
1343	 * Temperature is represented as a 10-bit code with a resolution of
1344	 * 0.25 degree celsius and encoded in two's complement format.
1345	 */
1346	temp = (temp_buf[0] << 8) | temp_buf[1];
1347	temp >>= 6;
1348	*mC = temp * 250;
1349
1350	return 0;
1351}
1352
1353static ssize_t ds3231_hwmon_show_temp(struct device *dev,
1354				      struct device_attribute *attr, char *buf)
1355{
1356	int ret;
1357	s32 temp;
1358
1359	ret = ds3231_hwmon_read_temp(dev, &temp);
1360	if (ret)
1361		return ret;
1362
1363	return sprintf(buf, "%d\n", temp);
1364}
1365static SENSOR_DEVICE_ATTR(temp1_input, 0444, ds3231_hwmon_show_temp,
1366			  NULL, 0);
1367
1368static struct attribute *ds3231_hwmon_attrs[] = {
1369	&sensor_dev_attr_temp1_input.dev_attr.attr,
1370	NULL,
1371};
1372ATTRIBUTE_GROUPS(ds3231_hwmon);
1373
1374static void ds1307_hwmon_register(struct ds1307 *ds1307)
1375{
1376	struct device *dev;
1377
1378	if (ds1307->type != ds_3231)
1379		return;
1380
1381	dev = devm_hwmon_device_register_with_groups(ds1307->dev, ds1307->name,
1382						     ds1307,
1383						     ds3231_hwmon_groups);
1384	if (IS_ERR(dev)) {
1385		dev_warn(ds1307->dev, "unable to register hwmon device %ld\n",
1386			 PTR_ERR(dev));
1387	}
 
1388}
1389
1390#else
1391
1392static void ds1307_hwmon_register(struct ds1307 *ds1307)
1393{
1394}
1395
1396#endif /* CONFIG_RTC_DRV_DS1307_HWMON */
1397
1398/*----------------------------------------------------------------------*/
1399
1400/*
1401 * Square-wave output support for DS3231
1402 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf
1403 */
1404#ifdef CONFIG_COMMON_CLK
1405
1406enum {
1407	DS3231_CLK_SQW = 0,
1408	DS3231_CLK_32KHZ,
1409};
1410
1411#define clk_sqw_to_ds1307(clk)	\
1412	container_of(clk, struct ds1307, clks[DS3231_CLK_SQW])
1413#define clk_32khz_to_ds1307(clk)	\
1414	container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ])
1415
1416static int ds3231_clk_sqw_rates[] = {
1417	1,
1418	1024,
1419	4096,
1420	8192,
1421};
1422
1423static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value)
1424{
1425	struct mutex *lock = &ds1307->rtc->ops_lock;
1426	int ret;
1427
1428	mutex_lock(lock);
1429	ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
1430				 mask, value);
1431	mutex_unlock(lock);
1432
1433	return ret;
1434}
1435
1436static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw,
1437						unsigned long parent_rate)
1438{
1439	struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1440	int control, ret;
1441	int rate_sel = 0;
1442
1443	ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1444	if (ret)
1445		return ret;
1446	if (control & DS1337_BIT_RS1)
1447		rate_sel += 1;
1448	if (control & DS1337_BIT_RS2)
1449		rate_sel += 2;
1450
1451	return ds3231_clk_sqw_rates[rate_sel];
1452}
1453
1454static long ds3231_clk_sqw_round_rate(struct clk_hw *hw, unsigned long rate,
1455				      unsigned long *prate)
1456{
1457	int i;
1458
1459	for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) {
1460		if (ds3231_clk_sqw_rates[i] <= rate)
1461			return ds3231_clk_sqw_rates[i];
1462	}
1463
1464	return 0;
1465}
1466
1467static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
1468				   unsigned long parent_rate)
1469{
1470	struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1471	int control = 0;
1472	int rate_sel;
1473
1474	for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates);
1475			rate_sel++) {
1476		if (ds3231_clk_sqw_rates[rate_sel] == rate)
1477			break;
1478	}
1479
1480	if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates))
1481		return -EINVAL;
1482
1483	if (rate_sel & 1)
1484		control |= DS1337_BIT_RS1;
1485	if (rate_sel & 2)
1486		control |= DS1337_BIT_RS2;
1487
1488	return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2,
1489				control);
1490}
1491
1492static int ds3231_clk_sqw_prepare(struct clk_hw *hw)
1493{
1494	struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1495
1496	return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0);
1497}
1498
1499static void ds3231_clk_sqw_unprepare(struct clk_hw *hw)
1500{
1501	struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1502
1503	ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN);
1504}
1505
1506static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw)
1507{
1508	struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1509	int control, ret;
1510
1511	ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1512	if (ret)
1513		return ret;
1514
1515	return !(control & DS1337_BIT_INTCN);
1516}
1517
1518static const struct clk_ops ds3231_clk_sqw_ops = {
1519	.prepare = ds3231_clk_sqw_prepare,
1520	.unprepare = ds3231_clk_sqw_unprepare,
1521	.is_prepared = ds3231_clk_sqw_is_prepared,
1522	.recalc_rate = ds3231_clk_sqw_recalc_rate,
1523	.round_rate = ds3231_clk_sqw_round_rate,
1524	.set_rate = ds3231_clk_sqw_set_rate,
1525};
1526
1527static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw,
1528						  unsigned long parent_rate)
1529{
1530	return 32768;
1531}
1532
1533static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable)
1534{
1535	struct mutex *lock = &ds1307->rtc->ops_lock;
1536	int ret;
1537
1538	mutex_lock(lock);
1539	ret = regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS,
1540				 DS3231_BIT_EN32KHZ,
1541				 enable ? DS3231_BIT_EN32KHZ : 0);
1542	mutex_unlock(lock);
1543
1544	return ret;
1545}
1546
1547static int ds3231_clk_32khz_prepare(struct clk_hw *hw)
1548{
1549	struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1550
1551	return ds3231_clk_32khz_control(ds1307, true);
1552}
1553
1554static void ds3231_clk_32khz_unprepare(struct clk_hw *hw)
1555{
1556	struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1557
1558	ds3231_clk_32khz_control(ds1307, false);
1559}
1560
1561static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw)
1562{
1563	struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1564	int status, ret;
1565
1566	ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &status);
1567	if (ret)
1568		return ret;
1569
1570	return !!(status & DS3231_BIT_EN32KHZ);
1571}
1572
1573static const struct clk_ops ds3231_clk_32khz_ops = {
1574	.prepare = ds3231_clk_32khz_prepare,
1575	.unprepare = ds3231_clk_32khz_unprepare,
1576	.is_prepared = ds3231_clk_32khz_is_prepared,
1577	.recalc_rate = ds3231_clk_32khz_recalc_rate,
1578};
1579
1580static const char *ds3231_clks_names[] = {
1581	[DS3231_CLK_SQW] = "ds3231_clk_sqw",
1582	[DS3231_CLK_32KHZ] = "ds3231_clk_32khz",
1583};
1584
1585static struct clk_init_data ds3231_clks_init[] = {
1586	[DS3231_CLK_SQW] = {
1587		.ops = &ds3231_clk_sqw_ops,
1588	},
1589	[DS3231_CLK_32KHZ] = {
1590		.ops = &ds3231_clk_32khz_ops,
1591	},
1592};
1593
1594static int ds3231_clks_register(struct ds1307 *ds1307)
1595{
1596	struct device_node *node = ds1307->dev->of_node;
1597	struct clk_onecell_data	*onecell;
1598	int i;
1599
1600	onecell = devm_kzalloc(ds1307->dev, sizeof(*onecell), GFP_KERNEL);
1601	if (!onecell)
1602		return -ENOMEM;
1603
1604	onecell->clk_num = ARRAY_SIZE(ds3231_clks_init);
1605	onecell->clks = devm_kcalloc(ds1307->dev, onecell->clk_num,
1606				     sizeof(onecell->clks[0]), GFP_KERNEL);
1607	if (!onecell->clks)
1608		return -ENOMEM;
1609
1610	/* optional override of the clockname */
1611	device_property_read_string_array(ds1307->dev, "clock-output-names",
1612					  ds3231_clks_names,
1613					  ARRAY_SIZE(ds3231_clks_names));
1614
1615	for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) {
1616		struct clk_init_data init = ds3231_clks_init[i];
1617
1618		/*
1619		 * Interrupt signal due to alarm conditions and square-wave
1620		 * output share same pin, so don't initialize both.
1621		 */
1622		if (i == DS3231_CLK_SQW && test_bit(RTC_FEATURE_ALARM, ds1307->rtc->features))
1623			continue;
1624
1625		init.name = ds3231_clks_names[i];
1626		ds1307->clks[i].init = &init;
1627
1628		onecell->clks[i] = devm_clk_register(ds1307->dev,
1629						     &ds1307->clks[i]);
1630		if (IS_ERR(onecell->clks[i]))
1631			return PTR_ERR(onecell->clks[i]);
1632	}
1633
1634	if (node)
1635		of_clk_add_provider(node, of_clk_src_onecell_get, onecell);
1636
1637	return 0;
1638}
1639
1640static void ds1307_clks_register(struct ds1307 *ds1307)
1641{
1642	int ret;
1643
1644	if (ds1307->type != ds_3231)
1645		return;
1646
1647	ret = ds3231_clks_register(ds1307);
1648	if (ret) {
1649		dev_warn(ds1307->dev, "unable to register clock device %d\n",
1650			 ret);
1651	}
1652}
1653
1654#else
1655
1656static void ds1307_clks_register(struct ds1307 *ds1307)
1657{
1658}
1659
1660#endif /* CONFIG_COMMON_CLK */
1661
1662#ifdef CONFIG_WATCHDOG_CORE
1663static const struct watchdog_info ds1388_wdt_info = {
1664	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
1665	.identity = "DS1388 watchdog",
1666};
1667
1668static const struct watchdog_ops ds1388_wdt_ops = {
1669	.owner = THIS_MODULE,
1670	.start = ds1388_wdt_start,
1671	.stop = ds1388_wdt_stop,
1672	.ping = ds1388_wdt_ping,
1673	.set_timeout = ds1388_wdt_set_timeout,
1674
1675};
1676
1677static void ds1307_wdt_register(struct ds1307 *ds1307)
1678{
1679	struct watchdog_device	*wdt;
1680	int err;
1681	int val;
1682
1683	if (ds1307->type != ds_1388)
1684		return;
1685
1686	wdt = devm_kzalloc(ds1307->dev, sizeof(*wdt), GFP_KERNEL);
1687	if (!wdt)
1688		return;
1689
1690	err = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &val);
1691	if (!err && val & DS1388_BIT_WF)
1692		wdt->bootstatus = WDIOF_CARDRESET;
1693
1694	wdt->info = &ds1388_wdt_info;
1695	wdt->ops = &ds1388_wdt_ops;
1696	wdt->timeout = 99;
1697	wdt->max_timeout = 99;
1698	wdt->min_timeout = 1;
1699
1700	watchdog_init_timeout(wdt, 0, ds1307->dev);
1701	watchdog_set_drvdata(wdt, ds1307);
1702	devm_watchdog_register_device(ds1307->dev, wdt);
1703}
1704#else
1705static void ds1307_wdt_register(struct ds1307 *ds1307)
1706{
1707}
1708#endif /* CONFIG_WATCHDOG_CORE */
1709
1710static const struct regmap_config regmap_config = {
1711	.reg_bits = 8,
1712	.val_bits = 8,
1713};
1714
1715static int ds1307_probe(struct i2c_client *client,
1716			const struct i2c_device_id *id)
1717{
1718	struct ds1307		*ds1307;
1719	const void		*match;
1720	int			err = -ENODEV;
1721	int			tmp;
1722	const struct chip_desc	*chip;
1723	bool			want_irq;
1724	bool			ds1307_can_wakeup_device = false;
1725	unsigned char		regs[8];
1726	struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
1727	u8			trickle_charger_setup = 0;
 
 
 
 
 
 
 
 
 
1728
1729	ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL);
1730	if (!ds1307)
1731		return -ENOMEM;
1732
1733	dev_set_drvdata(&client->dev, ds1307);
1734	ds1307->dev = &client->dev;
1735	ds1307->name = client->name;
1736
1737	ds1307->regmap = devm_regmap_init_i2c(client, &regmap_config);
1738	if (IS_ERR(ds1307->regmap)) {
1739		dev_err(ds1307->dev, "regmap allocation failed\n");
1740		return PTR_ERR(ds1307->regmap);
1741	}
1742
1743	i2c_set_clientdata(client, ds1307);
 
1744
1745	match = device_get_match_data(&client->dev);
1746	if (match) {
1747		ds1307->type = (enum ds_type)match;
1748		chip = &chips[ds1307->type];
1749	} else if (id) {
1750		chip = &chips[id->driver_data];
1751		ds1307->type = id->driver_data;
 
1752	} else {
1753		return -ENODEV;
1754	}
1755
1756	want_irq = client->irq > 0 && chip->alarm;
1757
1758	if (!pdata)
1759		trickle_charger_setup = ds1307_trickle_init(ds1307, chip);
1760	else if (pdata->trickle_charger_setup)
1761		trickle_charger_setup = pdata->trickle_charger_setup;
1762
1763	if (trickle_charger_setup && chip->trickle_charger_reg) {
1764		dev_dbg(ds1307->dev,
1765			"writing trickle charger info 0x%x to 0x%x\n",
1766			trickle_charger_setup, chip->trickle_charger_reg);
1767		regmap_write(ds1307->regmap, chip->trickle_charger_reg,
1768			     trickle_charger_setup);
1769	}
1770
1771/*
1772 * For devices with no IRQ directly connected to the SoC, the RTC chip
1773 * can be forced as a wakeup source by stating that explicitly in
1774 * the device's .dts file using the "wakeup-source" boolean property.
1775 * If the "wakeup-source" property is set, don't request an IRQ.
1776 * This will guarantee the 'wakealarm' sysfs entry is available on the device,
1777 * if supported by the RTC.
1778 */
1779	if (chip->alarm && device_property_read_bool(&client->dev, "wakeup-source"))
1780		ds1307_can_wakeup_device = true;
1781
1782	switch (ds1307->type) {
1783	case ds_1337:
1784	case ds_1339:
1785	case ds_1341:
1786	case ds_3231:
1787		/* get registers that the "rtc" read below won't read... */
1788		err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL,
1789				       regs, 2);
1790		if (err) {
1791			dev_dbg(ds1307->dev, "read error %d\n", err);
 
1792			goto exit;
1793		}
1794
1795		/* oscillator off?  turn it on, so clock can tick. */
1796		if (regs[0] & DS1337_BIT_nEOSC)
1797			regs[0] &= ~DS1337_BIT_nEOSC;
1798
1799		/*
1800		 * Using IRQ or defined as wakeup-source?
1801		 * Disable the square wave and both alarms.
1802		 * For some variants, be sure alarms can trigger when we're
1803		 * running on Vbackup (BBSQI/BBSQW)
1804		 */
1805		if (want_irq || ds1307_can_wakeup_device) {
1806			regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit;
1807			regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
 
 
 
 
 
1808		}
1809
1810		regmap_write(ds1307->regmap, DS1337_REG_CONTROL,
1811			     regs[0]);
1812
1813		/* oscillator fault?  clear flag, and warn */
1814		if (regs[1] & DS1337_BIT_OSF) {
1815			regmap_write(ds1307->regmap, DS1337_REG_STATUS,
1816				     regs[1] & ~DS1337_BIT_OSF);
1817			dev_warn(ds1307->dev, "SET TIME!\n");
1818		}
1819		break;
1820
1821	case rx_8025:
1822		err = regmap_bulk_read(ds1307->regmap,
1823				       RX8025_REG_CTRL1 << 4 | 0x08, regs, 2);
1824		if (err) {
1825			dev_dbg(ds1307->dev, "read error %d\n", err);
 
1826			goto exit;
1827		}
1828
1829		/* oscillator off?  turn it on, so clock can tick. */
1830		if (!(regs[1] & RX8025_BIT_XST)) {
1831			regs[1] |= RX8025_BIT_XST;
1832			regmap_write(ds1307->regmap,
1833				     RX8025_REG_CTRL2 << 4 | 0x08,
1834				     regs[1]);
1835			dev_warn(ds1307->dev,
1836				 "oscillator stop detected - SET TIME!\n");
1837		}
1838
1839		if (regs[1] & RX8025_BIT_PON) {
1840			regs[1] &= ~RX8025_BIT_PON;
1841			regmap_write(ds1307->regmap,
1842				     RX8025_REG_CTRL2 << 4 | 0x08,
1843				     regs[1]);
1844			dev_warn(ds1307->dev, "power-on detected\n");
1845		}
1846
1847		if (regs[1] & RX8025_BIT_VDET) {
1848			regs[1] &= ~RX8025_BIT_VDET;
1849			regmap_write(ds1307->regmap,
1850				     RX8025_REG_CTRL2 << 4 | 0x08,
1851				     regs[1]);
1852			dev_warn(ds1307->dev, "voltage drop detected\n");
1853		}
1854
1855		/* make sure we are running in 24hour mode */
1856		if (!(regs[0] & RX8025_BIT_2412)) {
1857			u8 hour;
1858
1859			/* switch to 24 hour mode */
1860			regmap_write(ds1307->regmap,
1861				     RX8025_REG_CTRL1 << 4 | 0x08,
1862				     regs[0] | RX8025_BIT_2412);
1863
1864			err = regmap_bulk_read(ds1307->regmap,
1865					       RX8025_REG_CTRL1 << 4 | 0x08,
1866					       regs, 2);
1867			if (err) {
1868				dev_dbg(ds1307->dev, "read error %d\n", err);
 
1869				goto exit;
1870			}
1871
1872			/* correct hour */
1873			hour = bcd2bin(regs[DS1307_REG_HOUR]);
1874			if (hour == 12)
1875				hour = 0;
1876			if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1877				hour += 12;
1878
1879			regmap_write(ds1307->regmap,
1880				     DS1307_REG_HOUR << 4 | 0x08, hour);
 
1881		}
1882		break;
1883	case ds_1388:
1884		err = regmap_read(ds1307->regmap, DS1388_REG_CONTROL, &tmp);
1885		if (err) {
1886			dev_dbg(ds1307->dev, "read error %d\n", err);
1887			goto exit;
1888		}
1889
1890		/* oscillator off?  turn it on, so clock can tick. */
1891		if (tmp & DS1388_BIT_nEOSC) {
1892			tmp &= ~DS1388_BIT_nEOSC;
1893			regmap_write(ds1307->regmap, DS1388_REG_CONTROL, tmp);
1894		}
1895		break;
1896	default:
1897		break;
1898	}
1899
 
1900	/* read RTC registers */
1901	err = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
1902			       sizeof(regs));
1903	if (err) {
1904		dev_dbg(ds1307->dev, "read error %d\n", err);
1905		goto exit;
1906	}
1907
1908	if (ds1307->type == mcp794xx &&
1909	    !(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {
1910		regmap_write(ds1307->regmap, DS1307_REG_WDAY,
1911			     regs[DS1307_REG_WDAY] |
1912			     MCP794XX_BIT_VBATEN);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1913	}
1914
1915	tmp = regs[DS1307_REG_HOUR];
1916	switch (ds1307->type) {
1917	case ds_1340:
1918	case m41t0:
1919	case m41t00:
1920	case m41t11:
1921		/*
1922		 * NOTE: ignores century bits; fix before deploying
1923		 * systems that will run through year 2100.
1924		 */
1925		break;
1926	case rx_8025:
1927		break;
1928	default:
1929		if (!(tmp & DS1307_BIT_12HR))
1930			break;
1931
1932		/*
1933		 * Be sure we're in 24 hour mode.  Multi-master systems
1934		 * take note...
1935		 */
1936		tmp = bcd2bin(tmp & 0x1f);
1937		if (tmp == 12)
1938			tmp = 0;
1939		if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1940			tmp += 12;
1941		regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR,
1942			     bin2bcd(tmp));
 
1943	}
1944
1945	ds1307->rtc = devm_rtc_allocate_device(ds1307->dev);
1946	if (IS_ERR(ds1307->rtc))
 
 
1947		return PTR_ERR(ds1307->rtc);
1948
1949	if (want_irq || ds1307_can_wakeup_device)
1950		device_set_wakeup_capable(ds1307->dev, true);
1951	else
1952		clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features);
1953
1954	if (ds1307_can_wakeup_device && !want_irq) {
1955		dev_info(ds1307->dev,
1956			 "'wakeup-source' is set, request for an IRQ is disabled!\n");
1957		/* We cannot support UIE mode if we do not have an IRQ line */
1958		ds1307->rtc->uie_unsupported = 1;
1959	}
1960
1961	if (want_irq) {
1962		err = devm_request_threaded_irq(ds1307->dev, client->irq, NULL,
1963						chip->irq_handler ?: ds1307_irq,
1964						IRQF_SHARED | IRQF_ONESHOT,
1965						ds1307->name, ds1307);
1966		if (err) {
1967			client->irq = 0;
1968			device_set_wakeup_capable(ds1307->dev, false);
1969			clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features);
1970			dev_err(ds1307->dev, "unable to request IRQ!\n");
1971		} else {
1972			dev_dbg(ds1307->dev, "got IRQ %d\n", client->irq);
 
 
1973		}
1974	}
1975
1976	ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops;
1977	err = ds1307_add_frequency_test(ds1307);
1978	if (err)
1979		return err;
1980
1981	err = devm_rtc_register_device(ds1307->rtc);
1982	if (err)
1983		return err;
 
 
 
 
 
1984
1985	if (chip->nvram_size) {
1986		struct nvmem_config nvmem_cfg = {
1987			.name = "ds1307_nvram",
1988			.word_size = 1,
1989			.stride = 1,
1990			.size = chip->nvram_size,
1991			.reg_read = ds1307_nvram_read,
1992			.reg_write = ds1307_nvram_write,
1993			.priv = ds1307,
1994		};
1995
1996		devm_rtc_nvmem_register(ds1307->rtc, &nvmem_cfg);
1997	}
1998
1999	ds1307_hwmon_register(ds1307);
2000	ds1307_clks_register(ds1307);
2001	ds1307_wdt_register(ds1307);
 
2002
2003	return 0;
2004
2005exit:
2006	return err;
2007}
2008
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2009static struct i2c_driver ds1307_driver = {
2010	.driver = {
2011		.name	= "rtc-ds1307",
2012		.of_match_table = ds1307_of_match,
2013	},
2014	.probe		= ds1307_probe,
 
2015	.id_table	= ds1307_id,
2016};
2017
2018module_i2c_driver(ds1307_driver);
2019
2020MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
2021MODULE_LICENSE("GPL");